high flow catalytic converter

**westwest888** · 03-13-2014 09:28 AM

I've read the information on this board about catalysts, and the information on the B7, B6 and B5 boards. I'm not sure what to make of it all. In theory and aftermarket downpipe could have a high end catalyst and exceed stock performance for both flow and cleaning the air that passes through it. It practice it may not be as reliable for as long. I would want to see +14 wheel horsepower to think this was worthwhile (from 371 HP at last dyno to 385 HP). The extra sound is great but not necessarily a plus nor a minus. My car is already flirting with the sound restriction at certain tracks.

Aftermarket, high end 300 cell catalytic converter for a 2.0TFSI.

Aftermarket vs. stock on a 4.2L S4

OEM Audi 600 cell, two stage catalytic converter (double catalyst for heating up fast, heating up slow) from a 2.0 FSI engine.

**drob23** · 03-13-2014 09:35 AM

http://www.audizine.com/forum/showth...tic-Converters

**westwest888** · 03-13-2014 09:42 AM

Originally Posted by drob23

http://www.audizine.com/forum/showth...tic-Converters

I respect CircuitTested about as much as I respect USA Today. It's cute and he's doing the best he can. That part may or may not be tainted.

There are other vendors with high quality parts on the market or coming to the market, with proven applications on other engines.

**NWS4Guy** · 03-13-2014 09:44 AM

It's possible to see gains, assuming the tune can take advantage of the increased airflow. Not sure if you would need a "test pipe" (i.e. Cat delete) file to take better advantage or not. The stock cats have a wicked sharp turn immediately after them, and the 034 HFC's have less of one for better airflow, but there was never any definitive gains shown, and some things pointed to poorer performance with these. Many also had to use spacers with the O2 sensor in order to get rid of CEL's, or use a test pipe file. The other big thing is that you have to either drop the engine or have someone who really knows things with special tools to get these swapped, they are wedged in just above the transmission at the top rear of the engine, and much like the headers install, nearly impossible to perform with the engine in the car due to space constraints.

http://www.audizine.com/forum/showth...B8-S4-3-0T-fsi!!!!!!!

**drob23** · 03-13-2014 09:55 AM

Originally Posted by westwest888

I respect CircuitTested about as much as I respect USA Today. It's cute and he's doing the best he can. That part may or may not be tainted.

There are other vendors with high quality parts on the market or coming to the market, with proven applications on other engines.

Just trying to give you a reference so you don't have to re-invent the wheel. I'm not aware of anyone else who makes HFC's for the 3.0T. I don't even see the 034's for sale anywhere. This is all I see from 034, which would be very "un-westwest" to run...would be much better saving the world with your Tesla:

http://store.034motorsport.com/produ...-3-0-tfsi.html

**drob23** · 03-13-2014 10:01 AM

Originally Posted by NWS4Guy

It's possible to see gains, assuming the tune can take advantage of the increased airflow. Not sure if you would need a "test pipe" (i.e. Cat delete) file to take better advantage or not. The stock cats have a wicked sharp turn immediately after them, and the 034 HFC's have less of one for better airflow, but there was never any definitive gains shown, and some things pointed to poorer performance with these. Many also had to use spacers with the O2 sensor in order to get rid of CEL's, or use a test pipe file. The other big thing is that you have to either drop the engine or have someone who really knows things with special tools to get these swapped, they are wedged in just above the transmission at the top rear of the engine, and much like the headers install, nearly impossible to perform with the engine in the car due to space constraints.

http://www.audizine.com/forum/showth...B8-S4-3-0T-fsi!!!!!!!

I thought the test-pipe files were simply there to remove certain CEL's from showing up? No actual difference in the tune?

**westwest888** · 03-13-2014 10:19 AM

I wonder if test pipes eliminate all of the back pressure and cause another issue that having a catalyst would mitigate.

**integroid** · 03-13-2014 10:25 AM

Originally Posted by drob23

I thought the test-pipe files were simply there to remove certain CEL's from showing up? No actual difference in the tune?

You are correct.

**IanCH** · 03-13-2014 10:41 AM

Changing your cats to increase power is like painting a pipe to stop it from leaking... Is 5hp worth all that trouble?

**NWS4Guy** · 03-13-2014 10:49 AM

Originally Posted by drob23

I thought the test-pipe files were simply there to remove certain CEL's from showing up? No actual difference in the tune?

I'm not certain if it just kills the O2 triggered CEL or if there is any other actual differences.

So far as these from 034, they posted videos then promptly removed (or made it private) them. The sound was pretty god awful, very raspy, harsh and not at all pleasant. There are videos on that thread I posted which have sound clips of a customer using the 034's with APR exhaust and it is not as bad as the original clips, but extremely loud under load. 034 claimed 22TQ and 20AWHP on stock exhaust (the broken links missing on the first post), however when these were taken to the track to prove what it showed in terms of actual useful performance, the times were almost always slower. After a lot of back and forth, 034 came back and said "the B8 crowd is too immature and not ready for something of this caliber, they don't understand what is being offered" and took the page and all reference to them down, refusing to sell them.

I'm sure if you call they will likely sell it if they still make and have any in stock, most of the best times on the slips sticky are people with these, but again they also have a lot of other mods, and some with the 034's are farther down on the list as well, so it's not really completely clear.

**Jake@JHM** · 03-13-2014 11:01 AM

Quality HFCs are definitely worth it if you are trying to squeeze power out of your engine. Will the performance be as good as test pipes? No. Would your butt dyno be able to tell the difference between Test pipes and quality HFCs? Chances are no.

Will quality HFCs give you better performance than stock cats? Yes.

**infinkc** · 03-13-2014 11:47 AM

i think you would be better off getting some 034 test pipes and adding the cats further downstream, if you flange them you could easily swap out for some test pipes.

**integroid** · 03-13-2014 11:49 AM

Originally Posted by NWS4Guy

I'm not certain if it just kills the O2 triggered CEL or if there is any other actual differences.

It is the same file with just the O2 triggered cel turned off.

**bwoy1981** · 03-13-2014 12:06 PM

Originally Posted by Jake@JHM

Quality HFCs are definitely worth it if you are trying to squeeze power out of your engine. Will the performance be as good as test pipes? No. Would your butt dyno be able to tell the difference between Test pipes and quality HFCs? Chances are no.

Will quality HFCs give you better performance than stock cats? Yes.

^^^^this, plus HFC are for ppl in states who require emission testing. In my B6, when the cat failed I did a testpipe and never looked back because we dont have emission testing here and I started focusing on power.

**SwankPeRFection** · 03-13-2014 12:24 PM

Originally Posted by westwest888

I wonder if test pipes eliminate all of the back pressure and cause another issue that having a catalyst would mitigate.

Backpressure isn't a concern with turbo applications. However, for NA and Supercharged (depending on output of the Supercharged application) ones need a bit. If you'd like to say Street Legal and have some kind of emissions test passing capabilities, you'll probably want to try a high-flow one and see what it gets you. In the past I've had custom ones built by Random Technologies and they've worked great, but make sure your tune is right or you will eat through them and have some loose cells in the exhaust in no time. Ask me how I know... lol

Anyway, I've always been an advocate of high-flow cats if built by a quality company and does show power improvement over stock setup while still maintaining some emissions controls. The only thing you'd have to worry on the S4 is if the ECU is calibrated in stock form to pick up a certain cleanliness of the exhaust throughout its warmup and operational stages. If the newly added higher flowing CAT doesn't clean up as many of the hydrocarbons as the OEM one, you will set a CEL. This of course can be taken care of by simply changing the expected limits of the O2 readout but not completely defeating them... so as to keep you in the know should the new CAT fully fail and you need to set the CEL for that issue... know what I mean?

All that said, only you can pick the right setup for you (no, I don't mean this tongue in cheek this time, lol). If you feel that you'd want to maintain a CAT based setup with some minor back pressure and get some gain as well, maybe the high-flow is for you. If not, either leave it stock or eliminate it. Hard to say what you'd get with a high-flow, but you should already know what removing the CATs gets you. I'd anticipate probably a 40-60% gain of that difference if you went with a high-flow CAT setup. Again, this is an estimate since there is still some restriction in there, but the percentages are within what I've seen on other applications.

**drob23** · 03-13-2014 12:33 PM

I wonder if APR will make a HFC for the 3.0T, they've done so on the A4 setup, especially with the Stg3 in the pipeline...

**CircuitTested** · 03-13-2014 01:30 PM

Originally Posted by westwest888

I respect CircuitTested about as much as I respect USA Today. It's cute and he's doing the best he can. That part may or may not be tainted.

First off, you're blatantly ripping off a project I started over three years ago. Second, you have absolutely zero experience other than the shallow level of knowledge you have gained by doing a few Club driving events. Third, you are more than welcome to dispute anything I've done. Strap on some of the new HFCs and let's see what you think.

**priceprince** · 03-13-2014 01:50 PM

Are the cats hidden enough on this car that you'll pass a visual inspection when you go to smog check your car here in CA? I'm sure the HFC would pass the sniffer test ok.

**NWS4Guy** · 03-13-2014 01:54 PM

Originally Posted by CircuitTested

First off, you're blatantly ripping off a project I started over three years ago. Second, you have absolutely zero experience other than the shallow level of knowledge you have gained by doing a few Club driving events. Third, you are more than welcome to dispute anything I've done. Strap on some of the new HFCs and let's see what you think.

I love you.

Originally Posted by priceprince

Are the cats hidden enough on this car that you'll pass a visual inspection when you go to smog check your car here in CA? I'm sure the HFC would pass the sniffer test ok.

They would have to even know what to look for. The stock cats can be seen from the engine compartment, but most shops are not going to know enough to know what the stock cats even look like, let alone if they are there. They likely are not even going to look for these unless you fail.

**priceprince** · 03-13-2014 03:28 PM

^thats what I figured, thanks

**Jake@JHM** · 03-13-2014 03:34 PM

The HFCs that we use across all of our platforms are a very high quality. While everyone in California knows that HFC are "Intended for off road use only" our customers report back to us all of the time stating that they passed out the pipe very cleanly. However, if the smog tech notices that it isn't the OEM cat you may have some issues.

**will13k7** · 03-13-2014 07:15 PM

why not stage 2 before HFCs?

**SwankPeRFection** · 03-13-2014 07:29 PM

Originally Posted by will13k7

why not stage 2 before HFCs?

lol, cuz Revo doesn't have Stage 2.

Or as West looks at the issue... Cuz Revo doesn't need Stage 2 to make the same amount of power his car does.

**budda** · 03-13-2014 07:32 PM

Only HFC I would use..... know several people running these and each has documented HP gains

http://www.hjsna.com/categories/HD-C...B47%7D-EURO-5/

**will13k7** · 03-13-2014 07:37 PM

Originally Posted by SwankPeRFection

lol, cuz Revo doesn't have Stage 2.

Or as West looks at the issue... Cuz Revo doesn't need Stage 2 to make the same amount of power his car does.

Time to switch to APR/GAIC, its just Revo SW that will get replaced right?

I haven't seen a plot of Revo's power-band, but I would like to believe a stage2 APR/GAIC setup will have more HP/Torque more of the time through-out the powerband, even at the top end. Does Revo get 16 PSI near the top end of the RPM range?

**audistealth** · 03-13-2014 07:38 PM

Does anyone know the stock flow rate? It's kind of important for comparative purposes.

**IanCH** · 03-13-2014 07:44 PM

I just want to mention that, from a laws of physics perspective, there is no fucking way that any tune that doesn't have a pulley makes anywhere near the power of a tune with the pulley.

And that's coming from someone with no real brand loyalty.

**will13k7** · 03-13-2014 08:11 PM

Seems like west is on the hunt for more power, no need to be loyal to Revo, time to make the switch! Okay, I'll stop derailing this thread now.

**helix139** · 03-14-2014 03:20 AM

Originally Posted by SwankPeRFection

lol, cuz Revo doesn't have Stage 2.

Or as West looks at the issue... Cuz Revo doesn't need Stage 2 to make the same amount of power his car does.

Yet he thinks his Revo tune is "conservative."

**NWS4Guy** · 03-14-2014 07:57 AM

Originally Posted by helix139

Yet he thinks his Revo tune is "conservative."

It is, didn't you see the numbers comparing race to pump gas?

**RudyH** · 03-14-2014 01:48 PM

I have these up if you are interested

http://www.audizine.com/forum/showth...ally-high-flow

**westwest888** · 03-14-2014 01:59 PM

Originally Posted by helix139

Yet he thinks his Revo tune is "conservative."

It is conservative. It's the same tune a dealer will sell you and it's capable of being warrantied, although the Revo route will save you $500 and contain no extended warranty. You can certainly purchase a 3rd party warranty to 100k miles and use an independent shop that can bill the guarantee company and not check for TD1 because they can't.

I will evaluate Revo Stage 2 if it becomes available to the US dealer network.

Sent from my Nexus 5 using Tapatalk

**NWS4Guy** · 03-14-2014 02:29 PM

Originally Posted by westwest888

It is conservative. It's the same tune a dealer will sell you and it's capable of being warrantied, although the Revo route will save you $500 and contain no extended warranty. You can certainly purchase a 3rd party warranty to 100k miles and use an independent shop that can bill the guarantee company and not check for TD1 because they can't.

I will evaluate Revo Stage 2 if it becomes available to the US dealer network.

Sent from my Nexus 5 using Tapatalk

I guess you missed the memo?

http://www.audizine.com/forum/showth...Stasis-no-more

**westwest888** · 03-14-2014 02:56 PM

Originally Posted by NWS4Guy

I guess you missed the memo?

http://www.audizine.com/forum/showth...Stasis-no-more

Yeah that was apparent years ago and I got laughed at for pointing out some of the subtleties of the Stasis and Revo partnership. That doesn't change all of the deployed software on thousands of people's cars or invalidate any of my statements about the tunes and their ability to conform to underwriter guidelines.

**IanCH** · 03-14-2014 03:01 PM

Originally Posted by westwest888

It is conservative. It's the same tune a dealer will sell you and it's capable of being warrantied, although the Revo route will save you $500 and contain no extended warranty. You can certainly purchase a 3rd party warranty to 100k miles and use an independent shop that can bill the guarantee company and not check for TD1 because they can't.

I will evaluate Revo Stage 2 if it becomes available to the US dealer network.

Sent from my Nexus 5 using Tapatalk

West says: commit fraud, If you know the guys helping you out its okay....

**westwest888** · 03-14-2014 03:11 PM

Originally Posted by IanCH

West says: commit fraud, If you know the guys helping you out its okay....

If you can pull one over on 3rd party sketchy mail order warranty company, you both win. Nothing in that contract says you can't modify the car. Auto finance, guarantee and reinsurance companies in and of themselves are ponzi schemes that blow up every other decade, particularly when the collateral is American cars produced in absurd volume.

I pay for my own service and take responsibility for my own vehicle. Some people fix whatever they can in their driveway and cry to the dealer looking for a freebie when they need a mod bailout. You won't find westwest888 in this situation.

**rynurz23** · 03-14-2014 05:50 PM

I'd like to add my 2 cents since I have run at the dragstrip with cats and with 034 test pipes. With cats, my fastest run was 11.87 @ 116mph without cats, my best was 11.67 @ 118mph Both runs were 100 octane gas and tune. Also Both days were at the same track with similar conditions, and DA's. Just for the heck of it, I'm planing on going to the Dyno soon to see if any increase shows up with the 034 TP's. It will be the same dyno that I did with the cats on.

**IanCH** · 03-14-2014 06:54 PM

Originally Posted by westwest888

If you can pull one over on 3rd party sketchy mail order warranty company, you both win. Nothing in that contract says you can't modify the car. Auto finance, guarantee and reinsurance companies in and of themselves are ponzi schemes that blow up every other decade, particularly when the collateral is American cars produced in absurd volume.

I pay for my own service and take responsibility for my own vehicle. Some people fix whatever they can in their driveway and cry to the dealer looking for a freebie when they need a mod bailout. You won't find westwest888 in this situation.

Actually, every single warrany offered by a third party has an explicit and strict clause that prohibits any modification to the car, even if it is not related to the claim at hand. I know this and have posted screen shots of the clause because I have read many of the available contracts.