B8 A4 DIY: Catalytic Converter Removal & HFC or Test Pipe Install

[Dan_Q]

This is really a pretty easy task if you have the right tools. I had read that it is a real PITA but I thought it was actually pretty simple. I ran into one problem requiring some cutting and drilling but had that not happened, I think I could do this in about 3 hours. From what I could tell, the process is virtually identical to what you do with the B6/B7 cars. You will need a helper for about 10 min which will make it 50 times easier than if you are trying to do it solo. They don’t have to get under the car or anything. It will help if they don’t have massive hands and forearms.

Step 1: Remove the auxiliary cooling fan shroud. Remove the airbox. Remove the turbo inlet hose. This is what you’re left with.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepA.jpg

Step 2: Disconnect both O2 sensors. The primary sensor wiring goes through a small clip on the exhaust manifold heat shield then the connector mates on a plastic bracket on the ignition coil harness assembly. The bracket and mating connector are shown below.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepB.jpg

You can then remove the primary sensor using an O2 sensor tool.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepB3.jpg

The secondary O2 sensor is routed between the aft of the engine and the firewall. The connector mate is done on a bracket installed to the driver’s side of the transmission. The picture below shows after I de-mated the connection. I had to spray a little WD-40 on the bracket in order to slide the connectors out of the bracket since it was a tight fit. It’s easier to safely de-mate the connectors after you have them off the bracket. There are two zip ties you will have to cut that tie the sensor wire down onto other wiring harnesses. After you disconnect it all you can route the sensor wire back to the cat in preparation for removing it.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepB2.jpg

Step 3: Remove the three nuts you can get to that connect the cat to the turbo using a 15 mm wrench. Spray them all down with PB Blaster. The two on the passenger side are easy to reach. I was able to get the upper driver’s side bolt using a normal 15mm craftsman combination wrench by alternating using the box end and open end in different orientations. None of the nuts were very tight but perhaps that is because my car only has 36k miles on it. In another 5 years perhaps they will be a lot tougher. You can see the 3 that I was able to remove in the picture below.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepC.jpg

Step 4: Remove the shock absorbing link assembly that connects the lower portion of the cat pipe to the engine. The lower bolt between the link and the engine will require a 12 mm combination wrench. The upper bolt (where the spring is) will require a 13 mm combination wrench from below to loosen the bolt and a 13 mm combination wrench from the top to hold the nut. You will need a helper from above to hold the nut because the way it is oriented you can't reach both sides and turning the bolt will just cause the nut to spin. When you reinstall this later you won't need a helper because the pipe is smaller and the bracket it mounts to is different so you will be able to reach both sides. Perhaps you can get the cat out with this link installed but the stock cat is a tight fit so I went ahead and removed it. You’ll need to remove it anyway once off the car because it will get installed to the new cat.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepD.jpg

Step 5: Disconnect the downpipe from the midpipe. You can see my connection below. Midpipe is to the right, downpipe is to the left. I had just installed a new exhaust (aft of downpipe) two weeks earlier. I didn’t use exhaust paste at this joint because I knew I’d be taking it apart in a week or two to do this project. That is why you can see the black marks indicating some exhaust had been escaping at this joint. Both clamp bolts on mine were 15 mm. I can’t recall if the bolts from the stock exhaust were 15mm or not. You’ll need a deep well socket to get over the bolts and onto the nuts. Once the connection is loosened you’ll need to slide the downpipe forward (it isn’t going to move much) and the midpipe backward to get the slip fit connection apart. I couldn’t get enough space so I had to remove the muffler hanger bracket so that the exhaust could be slid back farther. You'll probably have to do the same thing. Spray the connection down with some WD-40 to get the two sliding a little easier against each other.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepE.jpg

Step 6: Now you’ve got to get out the final nut holding the cat to the turbo. I rigged up the combination of sockets you see below and had a helper above help with getting the socket onto the bolt. The sequence was: 15mm deep well socket – swivel - 10” extension – swivel - 18” extension - 6” extension - ratchet. It would be damn near impossible to do this yourself. I suppose if you were stranded on a desert island and had a couple weeks to do this then you could probably do it yourself with only a 50:50 chance of hopelessly stripping the bolt. It took us a half dozen tries to get it on the nut securely but once it was on, the nut came right off.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepF.jpg

Step 7: Now you can pull the downpipe rearward so that the connection between it and the cat can be reached. Hopefully you’ve been spraying copious amounts of PB Blaster on these three nuts ever since you started the install because the nuts are cheap and they will be completely seized in place. I only got one of the three to come off. I think they are 12 mm. The other two got completely stripped. I broke out the dremel and cut the two bolts off. The problem I then realized is that the bolts are pressed into the downpipe flange and tack welded in place. So I couldn’t just hammer them out. I had to cut them flush with the flange and then drill them out. Then get replacement hardware. It wasn’t too bad because you have easy access to the spot but it was still a pain. Hopefully you have better luck than me and hopefully your cat comes with new nuts so you don’t have to put these three crappy ones back on, thereby virtually eliminating any hope of ever de-mating this connection in the future.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepG.jpg

Step 8: Now you should be able to wedge the cat out the top of the engine. It is a very tight fit with that secondary O2 sensor still installed, but it is so buried that you have no hope of getting it out with the cat in the engine bay. Just pull hard and get things oriented correctly and it will come out. Remove the secondary O2 sensor once you have it out of the engine bay.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepH.jpg

Transfer the secondary O2 sensor and the shock absorbing link over to the new cat. Installation is the reverse of removal, except that you’ll have more space to work with because your new high flow cat or test pipe is way smaller in diameter than the stock cat. I think if you are installing a test pipe that you can actually get all four of the TP to turbo nuts on from the top of the car. You should have gotten two new gaskets for either end of the cat and those will go in during the reinstall. Here is what your finished product is going to look like. Now go get a tune and start taking solace in the fact that your car is no longer slower than a V6 Toyota Camry.

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepI.jpg

[TCHUN003]

Awesome writeup. For step number 6, I made the EXACT same extension/swivel combo, but I wasn't able to do it. Instead, I ended up climbing on top of the engine and accessing that bolt from the top with a 10 inch extension/deep 15mm socket. Of course, I also needed someone to guide the socket/extension onto the bolt, but when we got it into place, it was quick! I agree that it wasn't very difficult to do.

[Ryan_T]

Excellent write-up.

Taking the bolts off seem like a complete pain.

[AlexDD]

Awesome! thank you!
On the step 6 I got my nut stripped. so I am running on stock cat on 3 bolts. the only thing I think I can do, is remove the turbo and get the bolt drilled out. Instead of doing the same labor as K04 install, I think I'll wait another 4-6 months until I go for an upgrade.
Or if you have an idea or suggestion how I might be able to get that f***in bolt out, please share that idea with me.

[Dan_Q]

Awesome! thank you!
On the step 6 I got my nut stripped. so I am running on stock cat on 3 bolts. the only thing I think I can do, is remove the turbo and get the bolt drilled out. Instead of doing the same labor as K04 install, I think I'll wait another 4-6 months until I go for an upgrade.
Or if you have an idea or suggestion how I might be able to get that f***in bolt out, please share that idea with me.

Nut stripped or bolt stripped? The only way you're going to get the nut off is by cutting it off, and for that the turbo needs to come off the car. The "bolt" it is attached to is actually a stud that is screwed into the turbocharger assy. The cat flange then goes over the opposite end of the stud and then the nut goes on to connect the two. So cutting through the bolt to get the nut off will by default, disconnect the cat from the turbo. Then you should be able to use an easy out to get the stud out of the turbo flange. Of course if you're replacing the turbo anyway, then you can just throw the whole mess in the corner of your garage and shout obsenities at it.

If it is the stud that is stripped then you're good to go. Remove the cat and you'll have plenty of room to work on getting that stud out of the turbocharger. Maybe just grind flats on either side of it so that you can get a wrench on it and then back it out after applying plenty of PB Blaster.

If you wanted to pull out the turbo just to fix this problem then it is probably around 6 hours of work. If you are paying for labor then it isn't going to be worth it. If you are doing it yourself then it's one Saturday of work. I guess it is up to you if that is worth it. If I was replacing the turbo in 4-6 months anyway then I'd just do it all at the same time.

[jordancl]

Dan based on your writeup it sounds like this was the same PITA for you that it was for me, except you have a better attitude lol

[simplicity]

Is it necessary to remove the airbox? Can I just remove the O2 sensor on top and then remove the 3 bolts then crawl underneath and remove the midpipe and remove the secondary O2 sensor then the "PITA" bolt?

How did you jack up the car and place on 4 jackstands? AFAIK there isn't a front or rear jackpoint on the vehicle....only the sides along the rails and there isnt enough space for my lift AND a jackstand.

Thanks, greaty DIY

[TCHUN003]

I just jacked the front end and held it up at the side rails with stands. Removing the airbox isn't NECESSARY, but it makes it A LOT easier, especially since removing the airbox only takes 2 minutes. There's only one bolt holding it on.

[simplicity]

Thanks, definitely the more space the better and in this case removing the airbox is simple enough to create more space. I was just planning to drive the fronts up my ramps but noticed Dan_Q's pic had the car in the air on 4 jackstands and it made me curious - kinda off topic.

[jordancl]

I'm able to get a jack and jackstands on the rails side by side its just really tight. You need to start with the jack as far to one side on the rail as possible.

[AlexDD]

Nut stripped or bolt stripped? The only way you're going to get the nut off is by cutting it off, and for that the turbo needs to come off the car. The "bolt" it is attached to is actually a stud that is screwed into the turbocharger assy. The cat flange then goes over the opposite end of the stud and then the nut goes on to connect the two. So cutting through the bolt to get the nut off will by default, disconnect the cat from the turbo. Then you should be able to use an easy out to get the stud out of the turbo flange. Of course if you're replacing the turbo anyway, then you can just throw the whole mess in the corner of your garage and shout obsenities at it.

If it is the stud that is stripped then you're good to go. Remove the cat and you'll have plenty of room to work on getting that stud out of the turbocharger. Maybe just grind flats on either side of it so that you can get a wrench on it and then back it out after applying plenty of PB Blaster.

If you wanted to pull out the turbo just to fix this problem then it is probably around 6 hours of work. If you are paying for labor then it isn't going to be worth it. If you are doing it yourself then it's one Saturday of work. I guess it is up to you if that is worth it. If I was replacing the turbo in 4-6 months anyway then I'd just do it all at the same time.

As I see it, and as the mechanic told me, the only way to fix that, is get the turbo off the car... so I decided to wait until the upgrade. the problem is, I can't wait! ;)

[simplicity]

Are there any torque settings for these bolts and the O2 sensors?

[espen4001]

Thanks for a great write-up! Did this last night, and your guide helped me out good :) Did not have a helper, so had to screw aroud a bit to get the last bolt on the turbo off, but did it with a single 15mm wrench :) Standing on top of the engine to get enough force to loosen it :)
And it was way easier to get the new cat in from under the car, somehow it would not enter from top, where I took out the old one. Might be worth a try to take the old one out underneatg also. It was a pretty tight fit to get it out from the top!


Are there any torque settings for these bolts and the O2 sensors?

55 nm for the O2 sensors, 40 nm for the 4 nuts connecting the cat to the turbo, 25 nm for the 3 nuts connecting front silencer and cat and 23 nm for the pipe clamp.

[accobra]

Hello Everyone I've been reading Audizine forums for a long time. I can't even begin to say how much I appreciate all the great posts. I wanted to thank Dan Q for the great DIY. This saved me a bunch of time and headaches installing the 034 HFC. I also used TCHUN003's method of removing the last bolt on the turbo and the rest was very straight forward.

[DJ_AudiA4]

Do you have to take off the nuts and the studs? Or does the cat just slide off after the four
nuts are off?

[van462]

Cat just slides off the 4 studs.

[DJ_AudiA4]

Cat just slides off the 4 studs.

cool, Thanks!

[B8on19s]

Nice write-up...

BTW, interesting to see that even ur CAT is "Made in South Africa" ....

[jbradle7]

http://i1112.photobucket.com/albums/k496/dqvale/K04%20Install/StepI.jpg

Thanks for the great write-up! The painted exhaust manifold looks very nice; what sort of prep did you do, what paint did you use?

[Dan_Q]

Thanks for the great write-up! The painted exhaust manifold looks very nice; what sort of prep did you do, what paint did you use?

I didn't paint it, I put in a new turbo/manifold at the same time.

[Alpha Ice]

Which HFC did you install? It looks like the SPM one

[DoItAllGarage]

I was wondering the same thing, which hfc?

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[Dan_Q]

Which HFC did you install? It looks like the SPM one

Eurocode

[Alpha Ice]

Nice! I'm glad to hear that, I'm looking to go that route and the AWE DP come springtime

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[Jeff P]

I just installed a 034 HFC yesterday, this writeup helped ALOT! Thank you Dan_Q

[Jerry1847]

Doing this next week, great writeup! I didnt have the O2 sensor or some of the longer 3/8 extenders so glad to get them and not be screwed when i do the job.

[Frinkferta]

Good luck! Spray those turbo bolts goooood!...with PB blaster that is.

[Jerry1847]

ill have my torch handy just in case :)

[Jerry1847]

For the secondary cat.... You can get it out with the O2 sensor tool, a flex joint, a long entension and rubber mallet.

Fit the sensor tool to the O2 with the square pointing to the driver side. Put the wratchet joint in with the long the long extension attached. The end not the extension will now be sticking out of the top of the engine. Hammer the top of the extension with the rubber mallet until the o2 sensor brakes loose. Remove the tool and you should be able to unscrew by hand. Boom!

I'm mid install. Everything went well so far. My 15mm deep socket wandered off so I'm trying to track one down for the last nut. I used a max access set/ combo wrench for the others with no issues.

[b6Hate4]

I just did this on Friday.

Holy shit that sucked! Had a lift, oxy acetelene torch, a helping hand and it still was not fun, and I'm no stranger to wrenching on cars, its just 1 bolt to the turbo and 1 bolt to the downpipe that snagged me up.

But I also used a roc-euro o2 spacer. 100+ miles later still no cel.

[A4 Centaur]

Dan you are still the best!

[Jerry1847]

QUOTE=b6Hate4;9591597]I just did this on Friday.

Holy shit that sucked! Had a lift, oxy acetelene torch, a helping hand and it still was not fun, and I'm no stranger to wrenching on cars, its just 1 bolt to the turbo and 1 bolt to the downpipe that snagged me up.

But I also used a roc-euro o2 spacer. 100+ miles later still no cel.[/QUOTE]

I got close with just a long extension and a wratchet. The missing deep socked was the issue. I got the socket on easy without a joint or wratchet attached. I'm thinking get get the socket on then the wratchet then blamo. I'll post an update later today after I give it a go.

[b6Hate4]

Getting the socket on is not the issue. Its getting the nut off without being able to put heat on the nut and being 100% sure your not stripping anything.

also the custom exhaust shop that did my exhaust welded the downpipe to the rest of the exhaust, so that made it alot more fun because there was no way to unclamp it.


And lastly, I put the Euro code on my car, and if you already have a cat-back, prepare for it to get throaty! My exhaust sounds amazing now.

[simek3ru]

I am doing this install this weekend and I only saw one mention of torque settings. Did anyone else bother to properly torque these bolts?

[Jerry1847]

I am doing this install this weekend and I only saw one mention of torque settings. Did anyone else bother to properly torque these bolts?

Nope, I don't bother with exhaust. Esp when you have 0 chance of getting a torque wrench on most of the bolts.

[simek3ru]

Thanks for the awesome DIY! What a pain that last nut on the turbo was. Ended up breaking it free with a 15mm combination wrench and another combination wrench for leverage.

Put in a 42 draft designs spacer but still have a CEL. If anyone else has this spacer, where are you pointing it?

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[BenA4B7]

Thanks for the awesome DIY! What a pain that last nut on the turbo was. Ended up breaking it free with a 15mm combination wrench and another combination wrench for leverage.

Put in a 42 draft designs spacer but still have a CEL. If anyone else has this spacer, where are you pointing it?

Sent from my HTC6525LVW using Tapatalk
Shit!
I was planning on installing the eurocode test pipe with the spacer.... So it's going to take à tune with that for the CEL!

[simek3ru]

Shit!
I was planning on installing the eurocode test pipe with the spacer.... So it's going to take à tune with that for the CEL!

Here's an update for you. I started the car up this morning to head to work and no CEL.

[richardm0025]

Awesome writeup. For step number 6, I made the EXACT same extension/swivel combo, but I wasn't able to do it. Instead, I ended up climbing on top of the engine and accessing that bolt from the top with a 10 inch extension/deep 15mm socket. Of course, I also needed someone to guide the socket/extension onto the bolt, but when we got it into place, it was quick! I agree that it wasn't very difficult to do.

You didn't use a swivel with that 10" extension? Doing install in the morning with a 6 pack of Three Floyds haha.

Thanks op for Diy

[spzavertnik]

The two times I have done this install, I was able to get around to the back bolt with a straight extension and use the space behind the engine to get it off. I reached under the cat and was able to guide the socket on with fingertips. I think I used a breaker pipe to initially pop the bolt loose without breaking my hand. Also, both times it took me probably 30 minutes of trying to get the cat out of the bottom instead of the top. The second time was just embarrasing once I realized what I did.

I have the angled roceuro spacer with the catalyst in it, and got a code on my first trip out of the neighborhood. I have since backed the spacer out a bit, so we will see if the CEL comes back once I get it cleared.

[richardm0025]

Well after a few beers in me, I thought this was the best idea to do it since I was by my self haha. I just stood in the engine bay and put a rope under that wrench and pulled up and that "PIA" nut came right off. I sure felt lucky, doing it this way took about 9 minutes total to get all 4 nuts off on the top end. I just took a grinder and cut the other end of the wrench off so it could fit underneath.
http://i1184.photobucket.com/albums/z335/richardm0025/IMG_2582.jpg (http://s1184.photobucket.com/user/richardm0025/media/IMG_2582.jpg.html)

http://i1184.photobucket.com/albums/z335/richardm0025/IMG_2581.jpg (http://s1184.photobucket.com/user/richardm0025/media/IMG_2581.jpg.html)

[Jerry1847]

Here's an update for you. I started the car up this morning to head to work and no CEL.
you still without CEL? I got one after ~45min. I clear it and it just comes back...

[Jerry1847]

The two times I have done this install, I was able to get around to the back bolt with a straight extension and use the space behind the engine to get it off. I reached under the cat and was able to guide the socket on with fingertips. I think I used a breaker pipe to initially pop the bolt loose without breaking my hand. Also, both times it took me probably 30 minutes of trying to get the cat out of the bottom instead of the top. The second time was just embarrasing once I realized what I did.

I have the angled roceuro spacer with the catalyst in it, and got a code on my first trip out of the neighborhood. I have since backed the spacer out a bit, so we will see if the CEL comes back once I get it cleared.

Did the same thing, deep 15mm on a ~10 or 15 in extension. Got the socket (w/ extension) on by hand then slowly attached a pivot and wrench with another extension on it. Came off with little force.

[Frinkferta]

Well after a few beers in me, I thought this was the best idea to do it since I was by my self haha. I just stood in the engine bay and put a rope under that wrench and pulled up and that "PIA" nut came right off. I sure felt lucky, doing it this way took about 9 minutes total to get all 4 nuts off on the top end. I just took a grinder and cut the other end of the wrench off so it could fit underneath.
http://i1184.photobucket.com/albums/z335/richardm0025/IMG_2582.jpg (http://s1184.photobucket.com/user/richardm0025/media/IMG_2582.jpg.html)

http://i1184.photobucket.com/albums/z335/richardm0025/IMG_2581.jpg (http://s1184.photobucket.com/user/richardm0025/media/IMG_2581.jpg.html)

Haha! Use PB blaster! It will loosen those nuts and makes the process WAY easier! A standard wrench and socket did it for me.


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[richardm0025]

That's exactly what I did haha yeah this is a great little DIY project!


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[simek3ru]

you still without CEL? I got one after ~45min. I clear it and it just comes back...

Yup, still without a CEL. About 200 miles so far. What spacer are you using?

[richardm0025]

Loving my new HFC. I actually feel like its a whole different car, no CEL but only driven it 15 miles. Def a lot of smoke from it braking in and maybe PB blaster haha?!

[Jerry1847]

Yup, still without a CEL. About 200 miles so far. What spacer are you using?

Argh! No spacer.
The stage 2 tune will eliminate the CEL right?
I started keeping an old netbook with the vagcom software in my car along with a set of emergency repair tools. Easy to clear The code.

[diego_demarco]

Quick question guys! I just got my 034 hfc in the mail today with my o2 sensor! I know the install shouldn't be that difficult but I'm always paranoid! I have a good shop (Wolfcar motorsports) in Miami that wants to charge my $330 plus tax to install it! But I have a local buddy (who did my vagcom mods) who offered to do it for $120... Now I just want to know what you guys think? Is it something that I should have the shop do? Or is it fairly simple?

[richardm0025]

Really if you have the right tools (just standard stuff any man should have) and two jack stands and your stock jack to lift up the car you can do it yourself. It's a bitch to do but better than spending the money on such a little thing. I found it fun though. You can get the four bolts off the cat. Using a standard wrench too.


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[richardm0025]

I also use a wrench on the o2 sensors as well.


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[diego_demarco]

Perfect thanks! I guess I'll let my friend do it for $120

[Jerry1847]

Perfect thanks! I guess I'll let my friend do it for $120

Good call. I would have def paid 120 for that install.

[oascom]

I was about do do it by myself... Got all the tools, Pb blaster etc... But then I called shop to ask how much they would charge me with tune together and they told me they will do it for 150+tune cost... I said fuck it for 150 it is wort it.

Lucky me! Shop spend 4h to get that shi.. out. All 4 bolts were stuck and corroded. They had to cut all of them and drill.

Still they charge me only 150 like they said before :)

[diego_demarco]

Yea if the difference was little then I would rather go to a shop lol but we're talking about $120 for someone local to do it or $330 plus tax for the shop to do it lol :/

[247ride]

Just installed a 034 HFC and all this info was super useful.

I ended up removing/installing the cat and downpipe through the top of the engine. I have a MT. No lift. Just jacked the car up , but was not high enough.

Obviously I ran into a few issues. The post cat O2 was a pain to remove. It worked only after really torching it. Heat it up really well and it will eventualy move. Having a special O2 sesor socket helps. And the bolts between the cat and downpipe were seized. I ended up just going to a neighbourhood shop and they removed the bolts for 15 bucks. Before stripping or cutting the bolts, this might save you some time.

[Tm030512]

Do you need "heat paste" on the bolts?? And are the nuts that come with the HFC good for heat?

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[Mod.Kill.Yut.]

Getting the socket on is not the issue. Its getting the nut off without being able to put heat on the nut and being 100% sure your not stripping anything.

also the custom exhaust shop that did my exhaust welded the downpipe to the rest of the exhaust, so that made it alot more fun because there was no way to unclamp it.


And lastly, I put the Euro code on my car, and if you already have a cat-back, prepare for it to get throaty! My exhaust sounds amazing now.

Any chance you can give us a vid so we can enjoy the amazing sounding exhaust as well? [:D]

[freshwun]

Just finished my Eurocode HFC install yesterday. Thanks for the instructions. It made the process a lot smoother. Some notes on my install:

1. I was able to remove both O2 sensors while the cat was still mounted.
2. I was able to get to the bottom driver's side turbo bolt from the top (lost the bolt while pulling it out)
3. Definitely need to remove the black plastic cover on the bottom of the car to access the hfc.
4. Broke one of the three threads that connected the hfc to the downpipe. Had to drill it out. Those bolts suck.
5. I was able to pull the original hfc out through the bottom of the car.
6. I installed the EC hfc from the top w/ the O2 sensors on.
7. Used original gaskets and nuts/bolts.
8. Had to replace the downpipe to midpipe clamp bolts/nuts because of rust.

Definitely noticed the car is more responsive. Haven't noticed a different in sound so far. CEL came on this morning while driving to work. Will get APR Stage 2 in the coming months.



2013 Audi B8

[Schrubbe8210]

Just installed a full turboback on my a4. thought i would share some info.

1. all 3 downpipe bolts i got off in about 3 minutes, you need long extensions, and you can get at all of them from the top through the engine bay. the driver side one did require one swivel joint, but even so came off easy.

2. if you take the advice in the post and get the rear o2 sensor out, it makes it a lot easier. put the o2 sensor crows foot on the sensor,plug a universal joint into the crows foot, then an extension into the uni joint, and then you can pound on the extension from the top of the engine to loosen the sensor.

3. with respect to the shock absorbing link, take off the 13mm bolt that goes into the rubber bushing first, since it doesnt have a nut on the other side, and then when you can move around the cat, you can get to the bolt/nut with the spring much easier. the cat also comes out of the car from the bottom much easier.

4. the lower inside turbo bolt is really easy to get at from the top of the engine, if you take a 3/8in ratchet, a 10in extension and a 15mm deep socket, and slip it in so the ratchet handle points up toward the hood. guide the socket with one hand, and then once it is on, you can get the nut off pretty easy.

I should have taken pics, but i always get so damn dirty i dont want to touch my phone.

Last but not least, at all, INSTALL THE NEW EXHAUST FROM THE FRONT TO THE BACK. There is not enough play in the system to weasel the pipes in between the resonators when you get them hung. I put the resonators on the bushings and then went back to put the connecting pipes in, and holy hell was that a bad idea.

it actually wasnt that bad overall.

[Mod.Kill.Yut.]

How bad would it be to drive the vehicle without the secondary O2 sensor for a day or so while I wait for my spacer to come in the mail?


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[o1turbo30v]

Pretty bad, just install it, its easy to get to.

[Mod.Kill.Yut.]

Pretty bad, just install it, its easy to get to.

How so?


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[o1turbo30v]

How so?


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Because you will have a hole in your exhaust after the cat, which means some of your exhaust gases will be getting blown into the engine bay and your interior air inlet which means you will be breathing in exhaust gases, your car will run like crap because every time you let off the gas you will create vacuum at that hole and bring air back in which will cause backfires or worse, your ecu will freak out, your front o2 will not be able to properly adjust your air fuel ratios because it is seeing air coming back into the system from the open hole in your exhaust, etc, etc. Just thread in the 2nd o2 and then remove it when you get your spacer, its right on the top...dont understand why you would not put the 2nd 02 sensor in?

[Mod.Kill.Yut.]

There is a plug on the cat where the O2 sensors go. I just left the plug in. I'm not worried about it because I have another car to drive so not of that stuff you just explained will occur regardless. Thanks for the insight though


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[Nastybutler]

Thanks so much for this How-To! Couldn't have done it without this. Managed to do it all myself in around 8 hours spread out over two days. Day one was removing it, day two was the install, which only took a couple of hours (I know I'm slow). Since my car has less than 6,000 miles on it I didn't have any issues with taking the nuts off either end (other than figuring out how to get enough torque to break the harder to reach ones), and I reused them as well as the gaskets (woe to the next sucker who has to take those nuts off; hopefully not me).

[Tm030512]

Thanks so much for this How-To! Couldn't have done it without this. Managed to do it all myself in around 8 hours spread out over two days. Day one was removing it, day two was the install, which only took a couple of hours (I know I'm slow). Since my car has less than 6,000 miles on it I didn't have any issues with taking the nuts off either end (other than figuring out how to get enough torque to break the harder to reach ones), and I reused them as well as the gaskets (woe to the next sucker who has to take those nuts off; hopefully not me).
Nice to hear it went well for you as well...mine had about 60k mils on it and I found it every easy to remove the bolts.....I got home one night and sprayed the bolts with some penetrating lubricant and extremely morning I did the removal and install no problem

[mkasperzak]

Thanks for the great write-up. Installed my EC HFC and AWE DP on Saturday with no major hiccups, took about 4.5 hours. I used the 10in extension and 15mm deep socket combo to get the 4th bolt (laying on engine) and it came right off. Only thing different for me was that 3 of the studs actually came out of the turbo with the nuts. I used vice and pressure clamps to remove old nuts from the studs and then re-installed studs into turbo.

Car feels great, definitely a little more umpff. Headed in tomorrow to go APR Stage II, but no codes right now with the 034 02 spacer. Wish the HFC/DP combo was a little louder with stock exhaust, but it is definitely a little throatier especially at WOT.

[boomtime]

Thanks for the great write-up. Installed my EC HFC and AWE DP on Saturday with no major hiccups, took about 4.5 hours. I used the 10in extension and 15mm deep socket combo to get the 4th bolt (laying on engine) and it came right off. Only thing different for me was that 3 of the studs actually came out of the turbo with the nuts. I used vice and pressure clamps to remove old nuts from the studs and then re-installed studs into turbo.

Car feels great, definitely a little more umpff. Headed in tomorrow to go APR Stage II, but no codes right now with the 034 02 spacer. Wish the HFC/DP combo was a little louder with stock exhaust, but it is definitely a little throatier especially at WOT.

It is louder and a little bit of a growl... I like it and will probably keep my stock exhaust for this reason.
Also after installing the 034 straight pipe I could hear the turbo spool faintly.

You are going to be surprised by stage 2, I was. Even more so if you had a flexfuel 2.0T [:D]
Even still I romped a G35 coupe with exhaust, from a roll-on the other day... on 93 (not e85). It would have been a slaughter with e85.

[inv3rtig0]

Thanks to this DYI my install went totally smooth. 2010 @ 44k miles

The 034 HFC looked very well made, and it fit perfectly. Accessed the bottom bolt by laying on the engine, was able to do it myself by getting the socket + extension on the nut then getting my arm behind the motor to attach the wrench. Used a breaker bar from the top. I could not get one of the bottom nuts back on with the combo wrench so I used a long ass extension and got it from the top. Also hit all the nuts/bolts with power blaster the night before, that stuff works magic. No O2 spacer, drove around the neighborhood and highway for a few minutes, no CEL yet. It feels like the turbo comes up a bit quicker, and I do like the sound, it has a subtle roar now when you have your foot in it. Great mod, now I need the stage 2!

Stock
http://i.imgur.com/48EcxtW.jpg

034
http://i.imgur.com/YPTtMnu.jpg

[helldriver]

I plan to do this install this spring , thanks for all the great imformation guys.....

[Fox Fader]

Got my Emusa installed today. Wasn't all that bad, all my bolts broke loose once I got the right setup on them. The 3 lower ones required a little pb and they broke loose. Up top, I got to the hardest bolt from up top through the rear of the engine like a previous poster stated. I left on the mid connetion mount and pulled it all out the top. Can't wait to drive it tomorrow

http://i120.photobucket.com/albums/o200/soulseeka/10%20A4/20150222_185116_zpsntltwdid.jpg

http://i120.photobucket.com/albums/o200/soulseeka/10%20A4/20150222_185138_zpsz1intr1f.jpg

[heffer]

Can anyone please give me advice on getting the nuts off the turbo loose? I tried getting mine off about a year ago and couldn't get the lower drivers side nut. I tried again the other day quickly but couldn't get any, this was without spraying pb blaster. Any advice would help!

[doowopaudi]

Any idea how much an indy shop would install this for? I'm referring to Audi Specialist (non-dealer prices) shop.

[boomtime]

Can anyone please give me advice on getting the nuts off the turbo loose? I tried getting mine off about a year ago and couldn't get the lower drivers side nut. I tried again the other day quickly but couldn't get any, this was without spraying pb blaster. Any advice would help!

Read my solution under step 6 (http://www.audizine.com/forum/showthread.php/626610-DIY-Q5-Downpipe-with-pics), it worked for me.

[Spm58]

Can anyone please give me advice on getting the nuts off the turbo loose? I tried getting mine off about a year ago and couldn't get the lower drivers side nut. I tried again the other day quickly but couldn't get any, this was without spraying pb blaster. Any advice would help!

I used PB Blaster then breaker bar and some extensions and went from up top behind the engine

[blbroo]

I used PB Blaster then breaker bar and some extensions and went from up top behind the engine

+1

[Nastybutler]

I used PB Blaster then breaker bar and some extensions and went from up top behind the engine

+2

[doowopaudi]

I was about do do it by myself... Got all the tools, Pb blaster etc... But then I called shop to ask how much they would charge me with tune together and they told me they will do it for 150+tune cost... I said fuck it for 150 it is wort it.

Lucky me! Shop spend 4h to get that shi.. out. All 4 bolts were stuck and corroded. They had to cut all of them and drill.

Still they charge me only 150 like they said before :)


Good to know. I hadn't read through all the posts. This is something I plan on getting installed the same day I get my Stage 2 this summer. $150 isn't bad at all.

[Fox Fader]

I used PB Blaster then breaker bar and some extensions and went from up top behind the engine

+3 but no pb or anything needed.

[b6Hate4]

Just torch the f**k out of those cat bolts. You wont hurt anything. I got them red hot then just spun them off very easily.

[heffer]

Just torch the f**k out of those cat bolts. You wont hurt anything. I got them red hot then just spun them off very easily.

Do you start cranking the bolts while they're still red hot?

[doowopaudi]

I was about do do it by myself... Got all the tools, Pb blaster etc... But then I called shop to ask how much they would charge me with tune together and they told me they will do it for 150+tune cost... I said fuck it for 150 it is wort it.

Lucky me! Shop spend 4h to get that shi.. out. All 4 bolts were stuck and corroded. They had to cut all of them and drill.

Still they charge me only 150 like they said before :)

I'm curious. Did you take it to a muffler shop or a EuroTuning Shop. When you say $150 + tune, what tune are you referring to?

Does anyone here see a problem with taking this job to a muffler shop? I would imagine they would charge much less than a eurotuner shop.

Update. It turns out a muffler shop isn't the best choice for this job because the catalytic converter isn't directly underneath the car. I'm gonna take in to a tuning shop.

[Spm58]

Does anyone know if the bolts going from the downpipe to the hfc are screwed in or how they're held in? I snapped one of them and tried getting banging it out but that didn't work, and the shops I asked want to change $100+ to drill it out

[blbroo]

I think they are bolt and nut. I snapped one having a brain lapse on lefty loosey and replaced it with a both and nut I had in my garage.

[Spm58]

Did it just slide/ fall out? Or was it held in there. I'm thinking of picking up more on blaster and just coating it and hammering it if it's supposed to slide out

[blbroo]

I think I had to encourage it out a bit, but not much. Just go under the car and look at the other side of that connection. If you see a bolt head, it's not a stud.

[Jerry1847]

Did it just slide/ fall out? Or was it held in there. I'm thinking of picking up more on blaster and just coating it and hammering it if it's supposed to slide out

I think the bolt/thread is welded to the midpipe. Just get some metal drill bits and drill it out. Replace with a new but/bolt.

[doowopaudi]

On which hole does the oxygen sensor go?
http://images.tapatalk-cdn.com/15/05/30/28a996efb831d900b1564c13b7faf999.jpg

[richardm0025]

On which hole does the oxygen sensor go?
http://images.tapatalk-cdn.com/15/05/30/28a996efb831d900b1564c13b7faf999.jpg

two oxy sensors. one in the front and one in the rear.

Also, I doubt that spacer will work to keep cel light from popping up if you don't get a tune. You might get lucky though.

[doowopaudi]

Shoot, I was supposed to buy two?

[goreckless]

two oxy sensors. one in the front and one in the rear.

Also, I doubt that spacer will work to keep cel light from popping up if you don't get a tune. You might get lucky though.

Huh????


Shoot, I was supposed to buy two?

You only need one spacer and it goes in the second one, post cat.

[richardm0025]

Shoot, I was supposed to buy two?

Oh, are you asking where does the oxygen sensor SPACER go? That would be the rear. You already have two oxygen sensors on the car. one will connect in front of the HFC and one will attach to the spacer which connects to the rear of the HFC.

[doowopaudi]

Thank You gentlemen yes I meant spacer

[goreckless]

Oh, are you asking where does the oxygen sensor SPACER go? That would be the rear. You already have two oxygen sensors on the car. one will connect in front of the HFC and one will attach to the spacer which connects to the rear of the HFC.

Oh I see now, my bad. I knew he meant spacer but didn't see he actually wrote sensor.

[richardm0025]

Oh I see now, my bad. I knew he meant spacer but didn't see he actually wrote sensor.

No worries


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[richardm0025]

Thank You gentlemen yes I meant spacer

Are you planning on a tune? I have that spacer and before I got a tune a couple months after I installed my hfc. When near Chicago the light would come on and when I was in Indy the light turned off lol. Let me know how it works out with that spacer.


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[doowopaudi]

Oh I see now, my bad. I knew he meant spacer but didn't see he actually wrote sensor.
It was my bad.

No worries


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Are you planning on a tune? I have that spacer and before I got a tune a couple months after I installed my hfc. When near Chicago the light would come on and when I was in Indy the light turned off lol. Let me know how it works out with that spacer.


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Yes, I plan on going stage 2 in July, but I plan on installing the HFC in the next week. I'll let you know.

[Shimmy]

so whats the point of installing the spacer when it seems like most people still get a CEL without the stage 2 tune?

[blbroo]

I have only popped a cel once with a spacer in 4 months


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[trackbaron]

Great write up! I'm looking at a primary cat-delete option. What's the difference between a test pipe and a downpipe? Is a test pipe just a catless downpipe? Can't seem to see the difference.

[Spm58]

Test pipe is a hi flow cat with out the cat, so it's just a hollow tube. The down pipe is what it bolts on to. Turbo, hfc, dp, rest of exhaust

[trackbaron]

Test pipe is a hi flow cat with out the cat, so it's just a hollow tube. The down pipe is what it bolts on to. Turbo, hfc, dp, rest of exhaust

Ok thanks for the clarification.

[The Infiltrator]

I have a 90° spacer on my 034 HFC and I've never had a CEL or issue in the four years of having it.

[Shimmy]

I have a 90° spacer on my 034 HFC and I've never had a CEL or issue in the four years of having it.

you also have a tune, no? i guess I'm wondering what the point is of getting the spacer when people are stage 2 anyways.

[The Infiltrator]

you also have a tune, no? i guess I'm wondering what the point is of getting the spacer when people are stage 2 anyways.

Yeah I've been stage 2 since 2011 and when I installed the HFC back then everyone said to add the spacer so I did. Not sure if you need it now with the new tune but it doesn't hurt to have.

[doowopaudi]

I think I'm gonna attempt this myself. I've called shops nearby and theyre all in the $150-180 range. May as well save that money for more mods right?

How many of you guys who did this yourself wish you would have had a shop do it instead?

[Spm58]

Doowopaudi it's a pain in the Ass. And that's an understatement. Make sure you have extensions for your ratchet and you'll probably want a breaker bar and I also suggest a ratcheting wrench, it works very well. I believe it's a 15 mm

[doowopaudi]

Doowopaudi it's a pain in the Ass. And that's an understatement. Make sure you have extensions for your ratchet and you'll probably want a breaker bar and I also suggest a ratcheting wrench, it works very well. I believe it's a 15 mm
Looks like I'll be taking a trip to Harbor freight for some tool shopping!

[trackbaron]

I was really pumped for this mod cause it's super inexpensive, but now the install has me second guessing. Anyone get a quote on the install from a shop? I'm going to get one tomorrow, hoping to compare it to something.

[The Infiltrator]

Looks like I'll be taking a trip to Harbor freight for some tool shopping!

It's not that bad if it's on a lift and you have the right tools.

[boomtime]

I think I'm gonna attempt this myself. I've called shops nearby and theyre all in the $150-180 range. May as well save that money for more mods right?

How many of you guys who did this yourself wish you would have had a shop do it instead?



I was really pumped for this mod cause it's super inexpensive, but now the install has me second guessing. Anyone get a quote on the install from a shop? I'm going to get one tomorrow, hoping to compare it to something.
If your second guessing it then pay the shop $180, its not for a first time mechanic but its also not that hard. The real danger is rounding off the turbo flange nuts or snapping a stud.
If $180 is too expensive then sell your Audi.


It's not that bad if it's on a lift and you have the right tools.

I only work with cars on my buddy's lift, at his shop with 20 years of accumulated tools.
When I was 20 years old I did everything on ramps or jack stands...and complained about having to buy a $5 socket to use once for that job...

[doowopaudi]

If your second guessing it then pay the shop $180, its not for a first time mechanic but its also not that hard. The real danger is rounding off the turbo flange nuts or snapping a stud.
If $180 is too expensive then sell your Audi.



I only work with cars on my buddy's lift, at his shop with 20 years of accumulated tools.
When I was 20 years old I did everything on ramps or jack stands...and complained about having to buy a $5 socket to use once for that job...
You're right, im gonna put it up for sale. Phew!

[S-Liner]

LOL

Nothing on these cars is difficult to R2...all you got to have is the patience, tools, and the desire to learn.

Anyone can disassemble shit, but taking it apart correctly is just as important as putting it back in.

Good luck, dude.


Sent from my iPhone 6+[emoji90][emoji90][emoji90]Trillion using Tapatalk

[Fburg A4]

I think I'm gonna attempt this myself. I've called shops nearby and theyre all in the $150-180 range. May as well save that money for more mods right?

How many of you guys who did this yourself wish you would have had a shop do it instead?
Do it man, don't be scared! On the diy scale this ranks pretty meh. But I think it depends on your resources. If you don't have a lot of tools (or experience) you may find yourself having some issues. Then there is the "uh oh" factor if something bad happens. Like somebody mentioned rounding off a bolt, do you have the tools to address that? Given that you are working on exhaust bolts, there is more of a chance of fastener issues than with other tasks. I've probably removed my cat like 10 times by now and never had a problem, but others have had uh oh moments.

But I am in the save your money camp with this task. My suggestion is that if you get a frozen bolt or are unsure what to do, just put things back together and don't force the issue.

[Nastybutler]

you also have a tune, no? i guess I'm wondering what the point is of getting the spacer when people are stage 2 anyways.

So when I flash it back to stock so it doesn't get TD1'd when I take it into the dealer for service it's not throwing a code.

[doowopaudi]

Do it man, don't be scared! On the diy scale this ranks pretty meh. But I think it depends on your resources. If you don't have a lot of tools (or experience) you may find yourself having some issues. Then there is the "uh oh" factor if something bad happens. Like somebody mentioned rounding off a bolt, do you have the tools to address that? Given that you are working on exhaust bolts, there is more of a chance of fastener issues than with other tasks. I've probably removed my cat like 10 times by now and never had a problem, but others have had uh oh moments.

But I am in the save your money camp with this task. My suggestion is that if you get a frozen bolt or are unsure what to do, just put things back together and don't force the issue.
Of course I'm gonna try it. $180 to remove 7 bolts, plus a diy thread??? This is a no brainer !

But yeah, if i get stuck, eveything goes back and I'll happily pay the shop[emoji4] [emoji106]

[Marko S]

Hey guy, I have a question that I couldn't find any answers too.

Im thinking about getting the 034 hfc with the O2 spacer. Was planning on running it on the stock exhaust with no tune. Is this even possible? Everywhere I've read people put the hfc after the tune and thats stage 2 i guess.

[doowopaudi]

Hey guy, I have a question that I couldn't find any answers too.

Im thinking about getting the 034 hfc with the O2 spacer. Was planning on running it on the stock exhaust with no tune. Is this even possible? Everywhere I've read people put the hfc after the tune and thats stage 2 i guess.
Yes it's possible. You'll get like 10-15hp

[Marko S]

Yes it's possible. You'll get like 10-15hp
Thanks man.


On another note does anyone here in ontario have any problems with hfcs and emissions? Another question i cant find an answer to

[boomtime]

Thanks man.


On another note does anyone here in ontario have any problems with hfcs and emissions? Another question i cant find an answer to

You shouldnt if you use the 90* spacer on the rear O2...so it wont set the CEL (telling them to replace your cat).
And since its permanent AWD they should not put it on the rollers...not sure if they do that up there or not either way.
We dont have inspection in Florida.

[Marko S]

http://images.tapatalk-cdn.com/15/06/19/64fea8634740375dadcdfaf29c23c0d8.jpg

So i purchased an 034 hfc from eurosporttuning in oakville and they were awesome. Im getting it installed sometime this week but have a question about the spacer. There are 3 different jets (on the top of the picture). Which one of these should I use? I've read 90* is best but dont know which is which.

I posted this question in another but got no response so I am posting here as I'd like to install this today. Thanks!

[bermudakid]

^ The smaller inserts are there to let you pick how much flow you want to get to the secondary 02 sensor. Pick one, if it works leave it if you still get a code go smaller.



Also you install this to the sensor on the HFC why would you install it today if you are getting the HFC installed later in the week??

[Marko S]

^ The smaller inserts are there to let you pick how much flow you want to get to the secondary 02 sensor. Pick one, if it works leave it if you still get a code go smaller.



Also you install this to the sensor on the HFC why would you install it today if you are getting the HFC installed later in the week??
I didnt want to get a code but i guess ill try the middle one. And sorry initially was going to get it installes next week but some time opened up today so going to do it today

[Fox Fader]

Here's the one I've been using for months with no ill effects at all. Got it on ebay, like $12.

http://i120.photobucket.com/albums/o200/soulseeka/10%20A4/20150222_185138_zpsz1intr1f.jpg

[SWONER]

This is what happens when you try to tackle this mod alone...http://images.tapatalk-cdn.com/15/06/22/1af9dcae9b186815792430d16aaa0358.jpg

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[boomtime]

This is what happens when you try to tackle this mod alone... http://images.tapatalk-cdn.com/15/06/22/1af9dcae9b186815792430d16aaa0358.jpg

Sent from my SM-G925V using Tapatalk

Poor cat from South Africa... Mine is going back on so I would never have cut it!

[richardm0025]

This is what happens when you try to tackle this mod alone...http://images.tapatalk-cdn.com/15/06/22/1af9dcae9b186815792430d16aaa0358.jpg

Sent from my SM-G925V using Tapatalk

Lol, you should have had a beer or two and have been more patient!


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[trackbaron]

Looks like you took a wrong turn somewhere mate lol

[blbroo]

This is what happens when you try to tackle this mod alone...http://images.tapatalk-cdn.com/15/06/22/1af9dcae9b186815792430d16aaa0358.jpg

Sent from my SM-G925V using Tapatalk

Maybe you should start your own HFC DIY. The "f#@& it" method.

[TommyK]

Damn i wouldn't think that was possible to shatter the metal like that

[blbroo]

Damn i wouldn't think that was possible to shatter the metal like that

Sure it will, when you hit it with one of these...

http://i17.photobucket.com/albums/b53/stoneygod/sawzall.jpg

[Fox Fader]

Wow! Didn't think I'd ever see that.

[bermudakid]

This is what happens when you try to tackle this mod alone...http://images.tapatalk-cdn.com/15/06/22/1af9dcae9b186815792430d16aaa0358.jpg

Sent from my SM-G925V using Tapatalk
Lmao.

Nice work! This is exactly how I imagined i would've done it on my own.

[Fburg A4]

wow, that is one way to do it! i applaud the creativity

[Smellie]

"Selling OEM Cat, Like new"

[richardm0025]

"Selling OEM Cat, Like new"

Lmao


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[boomtime]

"Selling OEM Cat, Like new"

JB WELD should hold that together no problem!

[Marko S]

Hey guys,

Got the 034 hfc installed and popped a CEL with the middle orifice. Going to get some help with it in the next couple of days, but in the mean time am I ok to drive with it?

[Fox Fader]

Hey guys,

Got the 034 hfc installed and popped a CEL with the middle orifice. Going to get some help with it in the next couple of days, but in the mean time am I ok to drive with it?

What's the middle orifice? If you'd just said you got a CEL, I'd say, yes, you can drive it safely.

[Marko S]

What's the middle orifice? If you'd just said you got a CEL, I'd say, yes, you can drive it safely.
Thankss. Umm there are 3 different sized jets (also called orifices) that can be inserted into the 02 extension.

[diego_demarco]

Contemplating getting an Hfc again to add to my awe dp and quad exhaust but not sure I feel like dealing with Cel's every other week :/

[KFizz]

Has anyone installed a testpipe and downpipe with the stock exhaust? I just finished installing a CTS testpipe with downpipe. I'm really surprised at how loud it is. I was expecting it to be louder than stock, but this is obnoxious. It sounds like a straight piped STI or something.

The fitment of the DP wasn't great. I had to do some trimming on one of the straight sections to get it to fit. Is it normal for this to be such a loud setup??

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[Marko S]

So I ran a test and got this code:

10434 - Catalyst System; Bank 1
P0420 00 [237] - Efficiency Below Threshold
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 4
Mileage: 63616 km
Date: 2015.06.24
Time: 19:03:24

Does this mean that there is not enough air flow going to the O2 sensor?

Also got these 2 faults:

4057 - Cylinder 2
P0302 00 [096] - Misfire Detected
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 63574 km
Date: 2015.06.23
Time: 11:52:07

4051 - Random/Multiple Cylinder Misfire Detected
P0300 00 [096] - -
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 63574 km
Date: 2015.06.23
Time: 11:51:31

I feel like this is due to the coils/spark plugs but could it be related to the hfc?

[boomtime]

It means the spacer isnt working,
The misfires are something else.

[Marko S]

It means the spacer isnt working,
The misfires are something else.
Thanks...
Do you think the misfires are due to the coils/spark plugs?

[boomtime]

Thanks...
Do you think the misfires are due to the coils/spark plugs?

It depends, you should clear the codes and then see if they come back right away or maybe after a certain driving condition.
From my experience its usually crappy gas.

[kskevin]

This thread was SOOOOO helpful. Couldn't have done the install without it. Got my HFC delivered Wednesday evening and did the install Thursday evening, flashed Friday to APR Stg 2 (e85). No helper for the install and was still able to complete in 3.5hrs. Thanks for the tutorial guys.

[oshwi]

So i just did this 10 mins ago, needless to say i sheared 2 bolts from the cat to midpipe. Should i be ok with just 1 bolt in the middle holding the thing? Im hearing a little drone. Is that normal? And yea, this thing is a freakin pain in the ass! Lol

[blbroo]

So i just did this 10 mins ago, needless to say i sheared 2 bolts from the cat to midpipe. Should i be ok with just 1 bolt in the middle holding the thing? Im hearing a little drone. Is that normal? And yea, this thing is a freakin pain in the ass! Lol

I wouldn't do that. Most of us that have the same issue drill the stud out and use generic hardware to hold it together.

[adamazing]

If anyone in Cali with an HFC is coming due for smog, please post up your experience.

Cali (finally) crossed over to the OBD diagnostic and replaced the actual measurement testing (which was supposed to be done two years ago). This means no more sniff testing. BUT there is still a detailed visual inspection. Since most HFC's have a strong third party look to them, I'd like to hear personal experiences and Smog testing success rates with them.

[Lambda13]

If anyone in Cali with an HFC is coming due for smog, please post up your experience.

Cali (finally) crossed over to the OBD diagnostic and replaced the actual measurement testing (which was supposed to be done two years ago). This means no more sniff testing. BUT there is still a detailed visual inspection. Since most HFC's have a strong third party look to them, I'd like to hear personal experiences and Smog testing success rates with them.

Could you paint it to make it look normal?

[blbroo]

Could you paint it to make it look normal?

Are you drunk Andrew? After a while, they change color to that brown / copperish tone that the stock one has when you take it off. I am not sure they would notice my HFC but the spaced out O2 sensor is obvious. Luckily, the guy that just installed my muffler mentioned that he doesn't go looking for trouble if the ODB2 scans ok on inspections.

[oshwi]

Hey blbroo, how hard was it to drill out? What equipment did you use? And did you take the midpipe out to do it? Thanks! Sorry for all the questions

[blbroo]

Hey blbroo, how hard was it to drill out? What equipment did you use? And did you take the midpipe out to do it? Thanks! Sorry for all the questions

I had the midpipe (downpipe) out anyway per the instructions I used. I just used a drill and a strong bit, didn't take much effort. The pipe is easy to get out once you have it disconnected from the cat, the other end is just in a slip joint.

[oshwi]

The nut and bolts on the slip joint is also corroded. I guess all the salt in nj just killed it. What a bother, dang.

[trackbaron]

Replace them and drive with peace of mind...

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[adamazing]

Could you paint it to make it look normal?

If it were to be an issue, I was thinking more along the lines of heat wrapping it.

[oshwi]

After some heating and a bunch of cussing, i finally got that stud from the mid pipe to cat removed. Thanks guys!

[Shaph]

One note for RHD models

You must remove the oxygen sensors in order to remove the cat.
It can only be removed from the top as the steering wheel column does not allow removal from underneath.
Use a tool pull to the cat from above such as a narrow pole and slowly pry forward.

[blbroo]

I think all models require the oxygen sensors to be removed since they are mounted to the cat...

Either way, good morning mate.

Holden Ute, so Aussie.

[boomtime]

I think all models require the oxygen sensors to be removed since they are mounted to the cat...

Either way, good morning mate.

Holden Ute, so Aussie.

Yes


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[Shaph]

I think all models require the oxygen sensors to be removed since they are mounted to the cat...

Either way, good morning mate.

Holden Ute, so Aussie.

yeah your are right cant see the cat coming out with the oxygen sensor on.
We love utes so much, wouldn't consider selling mine if it wasn't manual. They get so tail happy.

[jamesj2k]

Do you guys know if this DIY works on an Audi B8 S4?

[The Infiltrator]

Do you guys know if this DIY works on an Audi B8 S4?

Look at the DIY on the first page... you tell me. You have an S4, this is for an A4.

[jamesj2k]

MOST A4 diy's are same if not similar to S4's. Yes, I can read.

[trackbaron]

MOST A4 diy's are same if not similar to S4's. Yes, I can read.
For cosmetic things yes, but the exhaust systems on these two cars are entirely different. Removal of the converter out of the pipe should be similar but uninstalling the pipe is different.

[Lambda13]

Are you drunk Andrew? After a while, they change color to that brown / copperish tone that the stock one has when you take it off. I am not sure they would notice my HFC but the spaced out O2 sensor is obvious. Luckily, the guy that just installed my muffler mentioned that he doesn't go looking for trouble if the ODB2 scans ok on inspections.

I'm going to pretend I didn't make that post...


If it were to be an issue, I was thinking more along the lines of heat wrapping it.

Dammit it got quoted twice...

10-4 we're all clear. Nothing to see here people. Move on.

[The Infiltrator]

For cosmetic things yes, but the exhaust systems on these two cars are entirely different. Removal of the converter out of the pipe should be similar but uninstalling the pipe is different.

This!

[blbroo]

I am pretty sure that there is no performance benefit of HFCs on the b8 S4. Never see it talked about up there and have seen some old poor reviews of the 034 product.

The S4 forum is a much better place for the question than here.


^ I typed that with my thumbs! using tapatalk

[trackbaron]

FINALLY get to use this diy! Been shopping for awhile now but finally pulled the trigger. Seems like end of the season gave way to some good discounts and I'm super pumped to get this bad boy on!


http://www.audizine.com/gallery/data/500/testpipe2.jpg

[Lambda13]

Anyone have a link to the mini cat spacer? I can't recall who made it but I have a feeling I'm going to need one for emissions.

[trackbaron]

Anyone have a link to the mini cat spacer? I can't recall who made it but I have a feeling I'm going to need one for emissions.

+1 I'm on stock tune so I expect a cel without it. I'm guessing there are different sizes too.

[Lucid]

thx for the write up!!!!

my test pipe will be in any day!!!


ANYONE FROM AZ with vcsd tool?? i need to code my headlights :)

[heffer]

FINALLY got mine installed! It freaking sucked! But honestly I expected it. I definitely hear the turbo more now. I noticed a decent amount of power gain on my first run with it, I had my brother in the car so I'll be able to tell better tomorrow. Regardless, thanks for the DIY but I'll never attempt this install again! I'm on a stock tune BTW.
Oh I almost forgot. My car is smoking a good amount, PB blaster burning maybe?

[Townending]

Surprisingly, this was my only mod where I didn't have a single hiccup. Everything went smoothly.

It took 175 miles for my CEL to come on due to test pipe. No spacers.

http://i.imgur.com/6yNxtum.jpg

[trackbaron]

Surprisingly, this was my only mod where I a single hiccup. Everything went smoothly.

It took 175 miles for my CEL to come on due to test pipe. No spacers.

http://i.imgur.com/6yNxtum.jpg
What did you go with?

[Townending]

What did you go with?
Ebay test pipe. Only paid 60$.

It's been on for 4k miles so far, full throttle up to 150+MPH, no issues at all.

[lostkeyz]

Ebay test pipe. Only paid 60$.

It's been on for 4k miles so far, full throttle up to 150+MPH, no issues at all.
Are you still running a stock tune or using a spacer. I decided not to mess with the spacer anymore and go stage 2.


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[Townending]

Are you still running a stock tune or using a spacer. I decided not to mess with the spacer anymore and go stage 2.


Sent from my SAMSUNG-SGH-I537 using Tapatalk

I run Stage 2 on E85. My whole reasoning to get the ebay test pipe was to go from Stage 1 to Stage 2 as cheap as possible to hold me over until I'm ready for Stage 3.

-Test pipe : $60
-OEM Gaskets/Nuts : $20
-Labor Fee for Stage 2 flash : $55

Total Cost to go from Stage 1 to Stage 2 : $135

[heffer]

I have the 034 spacer and threw a cel already....

[Townending]

I have the 034 spacer and threw a cel already....

What's stopping you from getting a tune?

[heffer]

What's stopping you from getting a tune?
lack of funds. I will at some point, but don't know when that will be.

[Linksman72]

I just installed mine and noticed a lot of white smoke coming from the hfc area. I'm wondering too if it's the PB blaster burning off or something more serious

[boomtime]

I just installed mine and noticed a lot of white smoke coming from the hfc area. I'm wondering too if it's the PB blaster burning off or something more serious

Anything other than metal will burn off after 100 miles. The new ss pipe usually has a glaze from being made but also fingerprints and pb blaster will smoke too.

If anyone else is interested im selling my 3" SS TP and SS downpipe section to remove the pretzel resonator after the flex joint shoot me a PM. $200 for both pieces. 034 and USP...


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[RW12]

I haven't installed a HFC, but from having done other exhaust work, I would suggest after you install the pipe, spray it down with brake clean. That will remove most of the oil and grease and minimize smoking.

F*ck I love brake clean.

[julianwh]

Great write up, my mechanic friend and I were able to complete the install. That one bolt till about 15 mins to figure out and ended up getting it out with a short ratchet with the little space behind the engine. I'm very happy with the 034 & I feel like I have a new car. Sounds great and better pedal response. CEL came on almost immediately but I was expecting it. APR Stage 2 flash fixed it.

[Zactastic]

Should i disconnect the negative battery terminal or both + and - when doing this install? just curious if that helps for when i turn the car back on with the new cat to avoid CEL

[o1turbo30v]

Should i disconnect the negative battery terminal or both + and - when doing this install? just curious if that helps for when i turn the car back on with the new cat to avoid CEL

No, it won't help the CEL will eventually come on regardless, you have to go stage 2 from revo or apr.

[Zactastic]

No, it won't help the CEL will eventually come on regardless, you have to go stage 2 from revo or apr.

well, i do have a 90 degree spacer going in while i wait 2 more weeks for the RocEuro 45 degree spacer i have on back order. If i do get a CEL i guess ill have to go stage 2 :) If that's the case, when i do need to smog out here in CA, would i need to revert back to stock ECU? I am aware ill have to swap out the HFC for stock cat again at that point. the reason im hesitating going stage 2 is because of smog check. basically, would a stock cat with stage 2 be able to pass smog? I probably wouldnt want to drive it like that because of the stock cat restricting flow on stage 2 programing. please elaborate if you will, im clearing new at this [wrench]

[Zactastic]

Got it all hooked up except that "shock absorbing link assembly that connects the lower portion of the cat pipe to the engine" . it's at a slight angle, cant get the bolt threaded in there. anyone else have this issue and how did you resolve it? ill send a picture, right now it's attached to the cat only, no bolt in place.

[Zactastic]

http://uploads.tapatalk-cdn.com/20160403/70eb4618af10688906a619ede267a2a2.jpg.

http://uploads.tapatalk-cdn.com/20160403/5b3bb8bfb830d9b8289737e181c8d65c.jpg

Here's where I can't get the right angle for the bolt to engage and thread


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[lettuce]

Here's where I can't get the right angle for the bolt to engage and thread


Sent from my iPhone using Tapatalk

Have you tried unbolting it from the cat, bolting it up to the transmission and then trying to thread it onto the cat instead? I believe that's what I did and didn't have any issues.

[Zactastic]

Have you tried unbolting it from the cat, bolting it up to the transmission and then trying to thread it onto the cat instead? I believe that's what I did and didn't have any issues.

I loosened it from the cat to give it more play... but ill try your suggestion. thanks man. time for a beer after that!!

[earhythmic]

^^^figure that out and you can help me with mine when I go stage 2! I'm 5 miles away from you in Hercules 😬

[Zactastic]

^^^figure that out and you can help me with mine when I go stage 2! I'm 5 miles away from you in Hercules 😬

Nice man, ill be cleaning it up tomorrow morning and checking all the bolts again before i take her for a spin. This DIY thread really helps.

[Linksman72]

http://uploads.tapatalk-cdn.com/20160403/70eb4618af10688906a619ede267a2a2.jpg.

http://uploads.tapatalk-cdn.com/20160403/5b3bb8bfb830d9b8289737e181c8d65c.jpg

Here's where I can't get the right angle for the bolt to engage and thread



Sent from my iPhone using Tapatalk

I had this same problem a couple weeks ago, unscrew the link and rotate or flip it so the spring is attached facing the opposite direction. Attach it on the other side of the cat. It fits perfectly this way.

[Zactastic]

I ended up unscrewing it off the cat, gave it a slight bend, and it fit nice and snug.


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[Zactastic]

http://uploads.tapatalk-cdn.com/20160403/6e403f96dbe177740c35780b231008f9.jpg

http://uploads.tapatalk-cdn.com/20160403/59d751ff25969b7f4ca750835b35313b.jpg

Went for a spin, felt the added response and it sounds just bit deeper than stock. More noticeable in the sound when accelerating. I'm really happy with the 034 so far. Great DIY


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[Allowencer]

I'm just gonna leave this here:

https://scontent-yyz1-1.xx.fbcdn.net/hphotos-xpf1/t31.0-8/12983256_10154778902123508_1690569262250327463_o.j pg

[redeye_jedi]

Lol!!!!

[Zactastic]

PB blaster the crap out of it next time.


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[Allowencer]

Was not possible when the dealership rounded all of the nuts for whatever reason...

[earhythmic]

Just installed my HFC. Does any else have white smoke from the engine bay after install? I'm hoping it's just the PB blaster burning off, but maybe there's a leak somewhere? Almost looks like puffing from the turbo. Maybe not torqued enough?

[4ringnut]

Just installed my HFC. Does any else have white smoke from the engine bay after install? I'm hoping it's just the PB blaster burning off, but maybe there's a leak somewhere? Almost looks like puffing from the turbo. Maybe not torqued enough?

Yeah, it's the pb blaster burning off.

[kt883]

posted in the other thread about WG replacement but I found cat removal (namely the hidden bolt) wayyy easier with the 15mm deep socket on a 10" extension reaching behind engine/firewall and using my jack handle as breaker bar. I Was able to pull this off myself with no assistance. Hardest part is lining the socket up and not losing the bolt, having to line it up again. Putting that bolt back on is another tough job but makes it easy if you tape the nut in the socket and I could awkwardly slide my phone on video camera with flash mode so I could barely see what I was doing on the phone screen instead of blindly stabbing in the dark. Helped about 15% so worth a shot.

The other three bolts are easily broken free with a 15mm ratcheting combination wrench which makes short work of them. If your really having trouble on the other three use the 2 wrench trick but I didn't need it on mine. The drivers side top one is very easy its just that there is not a lot of sweep room (constantly readjusting after 1/8th of a turn is time consuming!) so that's where the ratcheting wrench comes in handy.

Can't explain how frustrating it was trying to pull cat out the top of the engine I furiously shook it in utter defeat after 20 mins of messing with it and it popped out lol. Has to be the perfect angle.

[poweredbyaudi7]

For reference in this thread! I am excited to try it....



Big thanks to Van462 for putting this DIY together. I tackled the job this mother’s day weekend despite not having any friends free to help out. I couldn’t wait and it seemed that every weekend was either raining, I was working or had something else that wouldn’t work so just said screw it and began. This was definitely the biggest job I have ever done with mk4 rad swap being my previous biggest job completed. It was intimidating but this thread and comments were all extremely helpful and encouraging.

I used a 15mm ratcheting flex head wrench for the cat bolts which worked wonders for all three once broken loose (used a TON of liquid wrench and Pb blaster). For the fourth bolt I could not figure out how to get that series of extensions from the bottom of car and was discouraged but I read the rest of the comments and saw mention of a 10” extension with a 15mm deep socket. Though it’s difficult to get it on the nut as you’re doing so blindly with limited hand access, I did get it after about 15 mins of screwing with it with the help of my jack handle as a breaker bar. Getting it back on is even harder but it helps to tape the nut into the socket so it doesn’t fall out. I used my phone video camera with flash on steady to peer at the screen tucked down there so I could sort of barely see what I was doing which helped out big time but is so awkward to manage by yourself. Pulling the Cat out the top is VERY frustrating!! I was ready to lose it when I violently wiggled it and it finally came out the top of the engine bay. You have to get the angle just right!
The wastegate bolts are pain to get at with the allen key but once broken loose you can undo and reinstall with your fingers. I elected to use my old WG actuator and shorten it as I noticed the actuator itself was strong but the door was loose by about 1/4” so shortening rod by ¼” as directed worked like a charm. Make sure you leave enough slack from the bracket as I cut too short and had to clamp it with pliers after extending rod with compressor to clear bracket enough to thread it.

I broke off all three downpipe bolts and could not drill through them with my drill and HSS drill bits (barely made a dent with my weight on drill!) so I took the exhaust off to get drilled by a machinist buddy. The exhaust clamp at the other end was completely seized with no hope so I just broke off those bolts too and it just fell apart. Had to hammer the socket on as they were so badly corroded around the area it didn’t allow it to just slip on. I’m currently running car with nothing after cat so its pretty loud lol my neighbors hate me. I finished at 11:30pm and anxiously started it up to test it but it was too loud to even leave my driveway at that time.
Next day I took it for a ride and SUCCESS! Car is boosting at 16 PSI peak (from 7psi!) and pulls hard. Exhaust roars at full throttle which is kind of nice, but draws a lot of attention. I will have some fun with it for a week or two then bolt it back up. Thanks again everyone who chimed in with advice.

Your best friend during this job
http://i66.tinypic.com/33af9fm.jpg

What I used to get that last hidden cat bolt
http://i67.tinypic.com/2hnz5ev.jpg

The tool in position
http://i67.tinypic.com/2q2r3x0.jpg

Comparison of old clogged cat with replacement - Likely clogged from stuck injector
http://i66.tinypic.com/2ziv9kk.jpg

[earhythmic]

55 nm for the O2 sensors, 40 nm for the 4 nuts connecting the cat to the turbo, 25 nm for the 3 nuts connecting front silencer and cat and 23 nm for the pipe clamp.

Going under the car again tonight to install the down pipe...is it really only 23nm for the pipe clamp? When installing my MF exhaust all the torque specs for the band clamps were 45 ft lbs...23 nm is only 16 ft lbs - a fly farts with more torque than that.

[kt883]

Those numbers sound like they should be in ft lbs, its all steel so I'd snug them a bit tighter, they will likely be seized on anyways just dont snap them.

[BIG_ROOSTER]

This is what happens when you try to tackle this mod alone...http://images.tapatalk-cdn.com/15/06/22/1af9dcae9b186815792430d16aaa0358.jpg

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That is how I will do mine way easier

[boomtime]

That is how I will do mine way easier

That's classy.

[Viperke]

The hfc is really that loud with stock exhaust??

[ECDT]

The hfc is really that loud with stock exhaust??

I have a hfc along with an awe dp and my wife couldn't tell that I changed those parts neither could my 9 month old. It is not loud with stock exhaust.


Sent from my iPad using Tapatalk

[hyperunion]

The hfc is really that loud with stock exhaust??
The new apr downpipe with the midpipe resonator delete was very quiet with the stock exaust!!!

Sent from my Nexus 7 using Tapatalk

[boomtime]

The new apr downpipe with the midpipe resonator delete was very quiet with the stock exaust!!!

Sent from my Nexus 7 using Tapatalk

How is that new apr downpipe kit?
Is it worth the $800?
Does it smell?

[hyperunion]

How is that new apr downpipe kit?
Is it worth the $800?
Does it smell?
It uses an American made 300 cel gesi hfc... It's definitely worth the 3 inch replacement midpipe....
No smell... I believe you run a test pipe on the q5?
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[boomtime]

It uses an American made 300 cel gesi hfc... It's definitely worth the 3 inch replacement midpipe....
No smell... I believe you run a test pipe on the q5?
Sent from my Nexus 7 using Tapatalk

No i run the stock cat. Testpipe was for the dyno.

[hyperunion]

No i run the stock cat. Testpipe was for the dyno.
You would definitely benefit running it

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[Dcferolino]

Have you had any cel so far when you installed the hfc and spacer

[Dcferolino]

Here's the one I've been using for months with no ill effects at all. Got it on ebay, like $12.

http://i120.photobucket.com/albums/o200/soulseeka/10%20A4/20150222_185138_zpsz1intr1f.jpg

So you have not had a cel at all when installing the spacer

[Fox Fader]

So you have not had a cel at all when installing the spacer

Not a one. Feb will be two years.

[Dcferolino]

Not a one. Feb will be two years.

I just tried the other spacer that i had its a longer 90degree angle so far ran 170miles no cel so i hope it stays that way


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[Fox Fader]

I just tried the other spacer that i had its a longer 90degree angle so far ran 170miles no cel so i hope it stays that way


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Good job!

[Dcferolino]

Good job!

Whats your setup on your engine can i view some pics


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[Fox Fader]

Whats your setup on your engine can i view some pics


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I'm all stock there. I have nothing to show.

[darkproduce15]

I'm all stock there. I have nothing to show.

Hey, i'm a new owner of a 2010 B8. You're completely stock with removing your catalytic, and just having a defouler? never did a flash on the ecu at all? My car is throwing a code for the catalytic, and i rather just get rid of it, than to get it replaced and pay $800+ bucks...

[Fox Fader]

Hey, i'm a new owner of a 2010 B8. You're completely stock with removing your catalytic, and just having a defouler? never did a flash on the ecu at all? My car is throwing a code for the catalytic, and i rather just get rid of it, than to get it replaced and pay $800+ bucks...

I never did a flash or code nor anything through Carista to make it work properly.

[keithk831]

Is it just me, or are all of the original pictures not displaying due to a 3rd party hosting feature being turned off?

[BIG_ROOSTER]

Is it just me, or are all of the original pictures not displaying due to a 3rd party hosting feature being turned off?

Photobucket FTW


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[Discipulus]

Is it just me, or are all of the original pictures not displaying due to a 3rd party hosting feature being turned off?

Yeah, photobucket seems to have killed just about all the pictures in all the DIY posts. Hopefully the OP can update the post and put pictures somewhere else? Dropbox perhaps?

[keithk831]

Yeah that would be great; I'm planning on doing this next weekend and pictures would be helpful.

[Hustalantavegas]

installed the 034 motorsports hfc that i picked up from waterfest today and let me tell you it was a real pita...I'm just getting home from the bar so excuse me for the venting Im about to do. To be honest it took me 7 hours but this incudes beers and breaks to swear and curse like a fool.

First let me start with the three nuts that hold the hfc to the flex pipe I was able to get the 2 visible bottom nuts of easily with a lot of pb blaster and a few minutes of heating with the propane torch (for my a5 these were not 15mm 12 or 13 cant remember). Tried to get the top one off but there is absolutely no room, hats off to those that can get this nut off..So after a brew I popped the socket on to a 30" extension and on my impact, I was able to pop the nut off easily sliding the extension down the top of the dump pipe on to the nut.
https://ibb.co/g7XCs5

The 3 nuts (2 passenger side and top drivers side) are pretty easy to get off with some pb blaster and a ratchet with 15mm socket, i have an obnoxious apr intake so removing that was a must. I was going to try DanQ's recommended combination of extensions and swivels but then I realized my dumb a55 only had one swivel. Luckily i was able to get the bottom drivers side nut off with a 15mm socket swivel and 20" extension easily without any stripping. I had to lay down flat on top of the engine first then slide the extension behind the engine by the firewall twisting it towards the nut as my right arm followed. I tried to hold the 15mm on the nut with my left hand as i grabbed my breaker bar and was able to snap it free.
https://ibb.co/edKxQQ

When it comes to the nuts that came with the 034 hfc and the size of the side that connects to the flex pipe, I was not able to get a socket to fit onto the top nut with the 30" extension as there is absolutely no space. My 15mm socket that fit before would not fit because the gap between the piping and nut was just too small. Not sure if anyone else ran into this issue or maybe it is because i got this hfc $50 off as it was the "show room special". Anyways for now i just have the bottom 2 nuts on if i cant get the top one on tomorrow i think I'll stop by a few shops and see if i can get them to agree to tighten that top nut before they know what they are getting into.

[ferndj02]

Thanks to all who contributed to this thread. Lots of great info here.

I definitely should have followed the advice of not snapping the studs on the downpipe. Getting the dp off and drilling out the stud was a complete pain in the ass. That thing was destroying drill bits. The clamp connecting the dp to the rest of the exhaust also had rusted completely so I had to cut those bolts off with an angle grinder.

I actually had a pretty easy time getting the HFC on and off the turbo... I guess I should have taken that as a sign of bad things to come.

Fun times!

[Richieru456]

Can any one repost the install pics?

[B8Brit]

Well that was a waste of MOTHER FUCKING TIME!!!!! Got the 4 turbo nuts off within 40 minutes. Got to take the bottom three off the flex pipe and they so damn corroded, not one size socket even fits. Gonna have to take it in to be done and I HATE that.


Neuspeed Power Module; Eurocode TIP; EBC slotted rotors & SS lines

[Richieru456]

Well that was a waste of MOTHER FUCKING TIME!!!!! Got the 4 turbo nuts off within 40 minutes. Got to take the bottom three off the flex pipe and they so damn corroded, not one size socket even fits. Gonna have to take it in to be done and I HATE that.


Neuspeed Power Module; Eurocode TIP; EBC slotted rotors & SS lines

Same problem I ended up having. Those and the downpipe-midpipe one. I’m going to try again tomorrow tho. I got 3 on top off. Still haven’t gotten the o2 sensor off but I’m not giving up lol

[B8Brit]

I’m just going to end up getting the CTS 3” down pipe...lol. Problem solved.


Neuspeed Power Module; Eurocode TIP; EBC slotted rotors & SS lines

[Richieru456]

I’m just going to end up getting the CTS 3” down pipe...lol. Problem solved.


Neuspeed Power Module; Eurocode TIP; EBC slotted rotors & SS lines

How did you get the fourth?

[Spawne32]

How did you get the fourth?

If you are talking about the 4th turbo bolt, the lower inwards one, a 12" extension with a deep socket, gotta hold your arm and hand down behind the motor and fish it on there blindly, once you get it on there, attach the ratchet and go to town. Although i admit it was the biggest bitch of the entire job next to all the studs breaking off from the mid pipe flange.

[Richieru456]

If you are talking about the 4th turbo bolt, the lower inwards one, a 12" extension with a deep socket, gotta hold your arm and hand down behind the motor and fish it on there blindly, once you get it on there, attach the ratchet and go to town. Although i admit it was the biggest bitch of the entire job next to all the studs breaking off from the mid pipe flange.

Got the 4th from the bottom but figures I would break a stud on the down pipe 🙄 taking it to a shop

[Spawne32]

Got the 4th from the bottom but figures I would break a stud on the down pipe 🙄 taking it to a shop

lol when all of mine broke i just ordered a whole new midpipe section from rockauto

[Richieru456]

lol when all of mine broke i just ordered a whole new midpipe section from rockauto

How much that run you? Thinking I mite just grab the usp downpipe and call it a day. I need it any ways so 🤷🏾*♂️

[Spawne32]

Walker 55633 $144.79

[B8Brit]

Walker 55633 $144.79

Ok...does that take the place of the huge suitcase resonator??


Neuspeed Power Module; Eurocode TIP; EBC slotted rotors & SS lines

[Spawne32]

Ok...does that take the place of the huge suitcase resonator??


Neuspeed Power Module; Eurocode TIP; EBC slotted rotors & SS lines

Yeh, its a whole new flex section and a 12" walker quiet flow ss muffler, make sure you buy the associated clamp for it. Chances are your oem clamp is gonna have to be cut off, mine was rusted solid.

http://www.hostthenpost.org/uploads/b9fb41226dcf7b21dd761af08b723f77.jpg

[IHave2Turbos]

i have a factory one for sale in classifieds as well

[Richieru456]

Walker 55633 $144.79

Mite just do a downpipe. Need it anyways

[Spawne32]

Mite just do a downpipe. Need it anyways

Well the downpipe and the mid pipe are two separate pieces, only ones I know of that sell aftermarket kits with both are APR and I believe unitronic. May be more out there but they will be much more expensive then just the HFC/dp portion.

[Richieru456]

Well the downpipe and the mid pipe are two separate pieces, only ones I know of that sell aftermarket kits with both are APR and I believe unitronic. May be more out there but they will be much more expensive then just the HFC/dp portion.

Wait, so the hfc is connected to what? The down pipe right? Now the stud broke on the pipe connected to the hfc, if that is the downpipe, couldn’t I just upgrade that and not the mid pipe? Just to clarify

[Spawne32]

Wait, so the hfc is connected to what? The down pipe right? Now the stud broke on the pipe connected to the hfc, if that is the downpipe, couldn’t I just upgrade that and not the mid pipe? Just to clarify

The downpipe is technically the portion with the cat, the part underneath with the first muffler is technically called the "mid section" or mid pipe. The term downpipe is thrown around pretty loosely around here but it generally it only refers to the section after the turbo that turns "down". lol