B7 Passenger Side Intercooler DIY

[Gosser]

I parted out a B7 a while back and tried to sell the whole kit for 100 bucks. No one bit, then I landed my 6spd, and it was the perfect 'free' upgrade before going to a large front mount. I know it has been documented a bit in the past, but the more information the better.

The parts I used from a B7 2.0T are the following:
059 145 814 B - B7 Intercooler bracket
8E0 145 806 M - B7 Passenger intercooler
8E0 145 708 K - B7 Passenger IC to cross over silicon piping
8E0 199 521 EB - B7 IC to IC metal cross over tube
8E0 117 336 N - B7 S-line Intercooler shroud (rev J is for non-sline bumpers) Regardless, I needed to cut it up. 8E0 117 336 C might not require cutting but not sure.
8E0 807 682 - Vented fog light grille, or modify your own, or grab them off ebay super cheap

A vented wheel well liner is also recommended but was never an options from the factory on the B6s. so you would have to graft one from a B5S4, a TT or a GTI 1JM 809 962 A, or anything really that had them.

You retain your stock turbo outlet silicon pipe, but need to modify the DV. I ended up relocating mine near the TB, which I have another chapter on elsewhere.

You will need to relocate your Secondary Air Injection(SAI) pump to facilitate this. Or you can completely delete it. The function of the SAI system is to help get the catalytic converter up to temperature faster in order to reduce start up emissions. This was required in order for the 1.8T to obtain a Ultra Low Emissions(ULEV) rating. If you just delete the SAI pump/hoses/install block off plate, you will end up with a MIL light. No amount of vagcomming can code this out. You will need to flash your ECU. This is primarily why I decided to keep mine for now.

The new location for the SAI ends up where the boost reservoir/Helmholtz resonator is mounted. The Helmholtz res gets deleted entirely. You will need shorter bolts to mount the new SAI mounting bracket, or cut the old reservoir bolts.

To start, you need to remove headlights, bumper and the rad support completely. Primarily because the IC to IC crossover tube needs to be swapped, and the power steering lines run through it and secondly it makes everything so much easier to work on. I left my AC lines connected, and worked around the condenser on the ground.

Start by making room for the SAI pump, this is the targeted location:

Everything removed:


I sourced a bracket from a A6 C5 : 8D0 906 615 B

You will need to cut up the bracket and drill one hole to get it to fit, I cut it a lot more than shown, and the hardware used is shown in the pic:

Then needed to tap an existing hole in the block, and you can see where my top bolt and nut combo is.

The original electrical harness will reach the new location. The SAI intake pipe needs to be lengthened about 8", and the outlet hose needs a 90 degree elbow cut into it. I used 3/4" heater hose for the intake pipe and gooed it together, and I used a 90 degree plastic PVC PEX fitting and glue it together. I am not looking to get 100,000km out of this set up so I am sure there some more permanent/indestructible solutions, but I digress:

This is the outlet pipe already installed:


Once the SAI is installed, it almost looks like it belongs there:


Once that is out of the way. Install the B7 IC gear. It all fits like OEM should and there really isnt anything to it. The turbo discharge only needs to rotate 90 degrees:


In the pics above, you can see a copper plug where the DV use to be. If you want to retain your stock location, you'll need to get a 90 degree 1-1/4" fitting and some heater hose to suite. I took this opportunity to relocate it closer to the TB.

Test fitting it all:


Lastly, you need to swap the cross over tube in the rad support. Here is the core with the B7 tube already installed:

Note the passenger side tube variance, the B7 points up and the B6 remains flat. I snapped both lower fan shroud bolts removing them...

Slam the core back on, and button up the front. Dont forget to top up the power steering fluid and boot it up. I never logged any data, but maybe I will beside one of my buddies cars that is still stock.

Here is the shroud that needs to be trimmed:


Before:

After:


And some reference diagrams:
B6:

B7:


I also attempted the B7 driver side IC swap as it has two additional rows, but deemed it not worth while. Documented in this thread, starts around post 11.

[Kevin C]

Nice, great write up!

[fR3ZNO]

Awesome! Great write up. I always wondered what was all involved to do this with B7 parts. There's an older DIY floating around, but the OP used new dealer parts from a BEX 1.8T that was only available in Europe, iirc.

Did you do any logs to show how much of an improvement there was?

[NaiveTurtle]

Awesome! I will be doing this in the near future. I have a set of 2.7T intercoolers sitting in my garage, but I may just try to make the extra B7 one work as I know someone who is in the middle of a 2.7T swap for their B7...

[Mattr567]

B6 1.8T with dual Smic? Am I stupid for asking if you can do the same with a B5?

Sent from my ONEPLUS A5000 using Audizine mobile app

[Gin+]

Note the passenger side tube variance, the B7 points up and the B6 remains flat. I snapped both lower fan shroud bolts removing them...

I gathered parts for this last week at the local yard and also snapped those bolts, I'm guessing it's a thing. The only item was I wasn't able to get was the turbo to intercooler hose but from the looks of it, I won't need it anyway.

Thanks for the write up!

[Gosser]

Nice, great write up!

Thanks

Awesome! Great write up. I always wondered what was all involved to do this with B7 parts. There's an older DIY floating around, but the OP used new dealer parts from a BEX 1.8T that was only available in Europe, iirc.

Did you do any logs to show how much of an improvement there was?

Yea, I felt the other write ups were kind of out dated, and some guys here asked me to post too. I havent logged anything yet, and never did any before. But I have a completely stock 1.8t, and between me and my buddies, there are another... i tried counting, but lets say at least 10 that i can do side by side comparisons on the same day. I'll wait for ti to warm up for that.

B6 1.8T with dual Smic? Am I stupid for asking if you can do the same with a B5?

I dont know the answer to that. Seems like the 2.7 had a dual set up, but I dont know how any of the piping was routed in that generation. Someone here on on the B5 section would be able to answer that quick.

I gathered parts for this last week at the local yard and also snapped those bolts, I'm guessing it's a thing. The only item was I wasn't able to get was the turbo to intercooler hose but from the looks of it, I won't need it anyway.

Thanks for the write up!

Np, let me know how it goes. I ended up drilling and tapping some new hardware in. I used some old thermostat hardware or something like that from the random bin. Are you keeping the SAI? What are you doing for the DV?

[Gin+]

I’m leaning towards coding the sai out and ditching it but I haven’t fully decided. As far as the dv goes, I’ll ditch the reservoir and attempt the elbow and longer hose. Not a big cobblery fan but if the shoe fits... K04 is the slow and steady goal.

[Luxus Panzer]

Sweet job dude. Great DIY write up as well.

[Wdries23]

I just did this upgrade to my b6, Very worthwhile upgrade, definitely better and cheaper than a crappy fmic, I paid under 100$ for all my b7 parts at the junkyard.

[Gosser]

Nice, happy to hear the thread still helps. My 6spd is still kicking around and taking all of the punishing I can throw at it! I did this mod at 273,000km, just about to roll over 300,000km!

[JDCinATL]

Today I finally sourced the last piece for this mod on my 02... passenger side duct. Seems most of the JY b7's are front end crashed around here, taking out bumper and duct. I'm not swapping the crossover tube, just using a 90deg silicone hose and a joiner piece to go to IC. Too much trouble to change the xover tube!

[Gin+]

I swapped out the crossover tube and it sucked, especially on the tiptronic with transmission cooler lines.

[Audi NASA Racer]

Impressive! I have a SMIC set up on my B5-using B5 intercoolers. Are the B6 & B7 units larger? My A4 is a track car-trying to lower AIT on hot days....

[Kevin C]

What are the dimensions of the current IC's that you have? There are aftermarket option for the B6 and B7 that just about double the capacity of the stock units.

[Audi NASA Racer]

Stock B5 intercooler core dims are: 2 5/8 deep, 6 3/4 wide and 9 1/2 tall.

[Kevin C]

Stock B5 intercooler core dims are: 2 5/8 deep, 6 3/4 wide and 9 1/2 tall.

Finally found my spreadsheet. Not all are a drop in. The ER B7 dual is for reference, the B7 left is not a good fit. Each has been written about and you should be able to find with some searching.

To compare FMIC core volume to DSMIC totalcore volume just add the volume of the two side mounts you are considering.

Side Mount Intercooler Core Sizes

Brand	Length"	Width"	Thickness"	Core Volume CI	Possible Combos	Combo Total
ER RaceWerks (B7 both sides)	10	7.3	3.5	255.5	2X	511
Tyrol (left)	10	8	4.5	360	Tyrol Left / Stock B7 Right	510
B6 Stock (left)	8.43	7.56	2.56	163	B6 Left + B7 Right	312
B7 Left	8.75	8.5	2.5	186	B7 L and R	335
B7 Right	8	7.5	2.5	150
Apikol Left side	8	8.1	3.5	226.8	Apikol Left / B7 Right	377
ER FMIC	20	11	3	660	Single FMIC	660
ER FMIC	18	6.5	3	351	Single FMIC	351
Custom Right	8	8.4	3.5	235	Custom Right / Tyrol Left	595

[Audi NASA Racer]

Wow-great data-thanks!

[DPDISXR4Ti]

I just did this upgrade to my b6, Very worthwhile upgrade, definitely better and cheaper than a crappy fmic, I paid under 100$ for all my b7 parts at the junkyard.

Do you have any data to support this statement? I realize "crappy fmic" is a bit vague, but I bet a lot of the fmic have greater volume than the two B7's combined.

Regardless, great thread Gosser! Thorough DIY posts with pics are the best!

[Gosser]

Thanks, happy to see the thread still going! Good data Kevin, surprised to see the B6/7 IC combo so low, but I guess stock is stock.

I've since sold the 6spd, but it was at 320,000km when I did, and still keep in touch with the new owner and he is loving it still with the Stage 1+.

[Justicar LeStat]

Did you have to shorten the crossover pipe to accommodate the 90 silicone hose?

[Justicar LeStat]

I am about to start gathering the parts for this mod. I will post my progress if anyone is still interested in the process 👍🏻

[EuroxS4]

I would personally be curious whether this mod is worth the reward and if there is data to back it up. Furthermore in regards to SAI I would just code it out by setting MSLUB map to zeros and call it a day.

[Kevin C]

I would personally be curious whether this mod is worth the reward and if there is data to back it up. Furthermore in regards to SAI I would just code it out by setting MSLUB map to zeros and call it a day.

I'm going out on a limb here and saying that the factory might have had a reason to use the duals on higher output cars....

I am in the process of upgrading my dual system from the B7 right, stock B6 left to a 2X larger right side and a 40% larger left side. Basicly a 288 ci in and a 224 cu in unit in series (512 cu in total). The B7 setup is has about 2x more area than a stock B6. This will get me about 1.6X more area than the B7 setup. One thing I have noticed is that a lot of aftermarket intercoolers are not very well optimized to distribute flow across the core. I have about 15 CFD runs on various configurations and its obvious that some designs are lacking. I also realize that certain inlet configurations are hard to optimize. Despite that I'm seeing 7 to 10% reduction in flow restriction and better distribution.

I will report back is its an improvement or not.

These are screen shots of last Sunday's work. These are first runs. Since then I have made some more progress and I'm getting a lot better at the new software package (Ansys Fluent).

20230723_170955.jpg20230708_153758.jpgScreenshot 2023-07-29 195633.jpg

[EuroxS4]

I'm going out on a limb here and saying that the factory might have had a reason to use the duals on higher output cars....

I am in the process of upgrading my dual system from the B7 right, stock B6 left to a 2X larger right side and a 40% larger left side. Basicly a 288 ci in and a 224 cu in unit in series (512 cu in total). The B7 setup is has about 2x more area than a stock B6. This will get me about 1.6X more area than the B7 setup. One thing I have noticed is that a lot of aftermarket intercoolers are not very well optimized to distribute flow across the core. I have about 15 CFD runs on various configurations and its obvious that some designs are lacking. I also realize that certain inlet configurations are hard to optimize. Despite that I'm seeing 7 to 10% reduction in flow restriction and better distribution.

I will report back is its an improvement or not.

These are screen shots of last Sunday's work. These are first runs. Since then I have made some more progress and I'm getting a lot better at the new software package (Ansys Fluent).

20230723_170955.jpg20230708_153758.jpgScreenshot 2023-07-29 195633.jpg

Great work Kevin, I'm not doubting whether in fact that setup works, just saying one should weigh the pros and cons and cost effectiveness vs a giant 3 pass FMIC or Air to water setup at the end of the day it comes down to cost and gains in terms of power or decrease in intake temps.

[Kevin C]

Great work Kevin, I'm not doubting whether in fact that setup works, just saying one should weigh the pros and cons and cost effectiveness vs a giant 3 pass FMIC or Air to water setup at the end of the day it comes down to cost and gains in terms of power or decrease in intake temps.

Thanks,

I understand what you are are saying on the JY retrofit. For sure its cost effective since its just a matter of sourcing JY parts (I spent about $100). On my setup the IAT are higher than I would like so I'm upgrading. At 22 psi I'm getting too much timing pull on hot days. I really don't need the ultimate, I just need better. Lots of ways to get there. I would rather not cut the front crash bar or substitute a fabbed piece of steel. I agree the an air to water is a good solution. For now I'm going with the simple no moving parts air to air. That and I'm having a lot of fun with the CFD simulations.

Some of the aftermarket setup get prett pricey.

[EuroxS4]

Thanks,

I understand what you are are saying on the JY retrofit. For sure its cost effective since its just a matter of sourcing JY parts (I spent about $100). On my setup the IAT are higher than I would like so I'm upgrading. At 22 psi I'm getting too much timing pull on hot days. I really don't need the ultimate, I just need better. Lots of ways to get there. I would rather not cut the front crash bar or substitute a fabbed piece of steel. I agree the an air to water is a good solution. For now I'm going with the simple no moving parts air to air. That and I'm having a lot of fun with the CFD simulations.

Some of the aftermarket setup get pretty pricey.

I agree. Air to water is nice but can get pricey and the need for some plumbing also take up real estate as well. I am currently mocking up a garrett 600fmic core it looks like it will fit behind the stock bumper without the need to cut the crash bar. Just needs to be mounted a little higher and some trickery to get airflow into the top portion of the core. Minor trimming needed.

[Kevin C]

Decided to try using an Apikol left side intercooler to replace the OEM B6 unit. That will be paired up with my custom right side unit. The folks at Apikol were super cool and sold me theparts so that I can experiment with the CFD analysis to look for possible efficacy improvements. That will allow me to add flow directors and then weld the unit up.

Very nice core, it looks to be a Bell. The cast tanks are a nice touch.

20230731_184118.jpg