Turbo Upgrade Questions

[DALLAS_RS6]

So here we are again with the question of upgrading turbos. As some of you know, I'm trying to complete my stage 4 MTM tune by doing the turbos and downpipes. I want to upgrade turbos without reconstructing the whole induction and exhaust. So far the only thing I found is the 034 waste gate modification which allows the waste gate to open up at 12 psi instead of 6 which in turn is suppose to allow more boost. There is also the Vast performance billet wheel upgrade which puts in a .59 billet wheel in our turbos and takes the waste gate up to 14 psi. I would like some input on these modifications. Are they safe/reliable? Anybody know anyone who's had them?

[DHall1]

The problem with adding bigger wheels comes into play in the center section. Can the center section take the added cross sectional loads from the larger wheels?

In addition, the major cap on flow in the RS6 turbo is the size of the turbine housing. You just cant get around the physical a/r ratio in that turbine housing. There in lies the rub. You need larger turbine (hot side) housings in the turbo not just bigger wheels.

I would max out the current state of tune and make sure everything is working as designed. That means get over to the scope and dyno that bad boy. At the same time complete some data logs and send them to me. I have a ever growing file of data logs as far as the eye can see. Make sure you are putting down what we know a good Stage2 RS6 should be putting down.

[DALLAS_RS6]

The problem with adding bigger wheels comes into play in the center section. Can the center section take the added cross sectional loads from the larger wheels?

In addition, the major cap on flow in the RS6 turbo is the size of the turbine housing. You just cant get around the physical a/r ratio in that turbine housing. There in lies the rub. You need larger turbine (hot side) housings in the turbo not just bigger wheels.

I would max out the current state of tune and make sure everything is working as designed. That means get over to the scope and dyno that bad boy. At the same time complete some data logs and send them to me. I have a ever growing file of data logs as far as the eye can see. Make sure you are putting down what we know a good Stage2 RS6 should be putting down.

I definitely get what your saying. I'll work on getting some data logs to see if I'm even using max boost with the current turbos. Maybe all I need to do is make my turbos more efficient by ceramic coating them and polishing the turbo exhaust, also ceramic coat and port/polish the exhaust manifolds.

[DHall1]

Vag com data log

3,31,115...select "turbo" mode before starting to log.

Find a dead end road safe to drive 95mph and slow down after.

1. 2 or 3 runs from a standing start thru 3rd gear.
2. Rolling with tip in 3rd gear at 2800rpm and then hit WOT to redline.

Send logs to me. ;-)

[as350]

OK, I'm going to show my lack of knowledge with the following question.

I also own an 01 Audi TT 225 which has a K04 (-23, I think) just like our beasts. I run APR software on my TT along with a few intake and exhaust modifications along with a manual boost controller. My setup allows for peak boost around 22 psi. The K04 will go higher, but at 26 the ECU goes into limp mode and IATs go hot rapidly with higher boost. I know TT owners that are running over 30 psi on a stock K04, but they also have massive intercoolers, w/m injection, different waste gate actuator springs and custom tunes to make it all work.

So, if the K04 turbos are proven to work at much higher boost, why not swap the RS6 turbos with TT turbos instead of trying to tweak turbine wheels etc.? Is the geometry different and intake/exhaust don't line up?

[1sadavant]

Couple of options:

1) http://www.eplabs.net/products/vag/r...t-upgrade-kit/

2) Contact Vast or Blouch Turbo (http://www.blouchturbo.com/) about modifying the wheels. As the aforementioned post hinted, changing the wheels may or may not affect the CHRA. I am sure either of these shops can address this, and I highly doubt it's a problem, plenty of K04-025/K04-026 (OEM RS4) turbos are modified with OEM RS6 wheels and CHRA's as well as OEM Porsche 997 compressor wheels.

AS350: Your "K04-23" turbo on the TT is not the same as the k04-028 & k04-029 OEM turbo on the RS6. The 23 vs. 28/29 flow characteristics are drastically different, and understandably considering a 4 cylinder vs. 8 cylinder.

3) Not sure what turbos EPL uses (most likely TIAL 605's or 770's) but considered something of this gt variant. Unfortunately, not many if any here have upgraded their turbos, but it's difficult to find a bolt-on turbo for this platform because of the tight engine bay confines and the exclusivity of the model.

Look forward to hearing what you find out.

[Brav]

OK, I'm going to show my lack of knowledge with the following question.

I also own an 01 Audi TT 225 which has a K04 (-23, I think) just like our beasts. I run APR software on my TT along with a few intake and exhaust modifications along with a manual boost controller. My setup allows for peak boost around 22 psi. The K04 will go higher, but at 26 the ECU goes into limp mode and IATs go hot rapidly with higher boost. I know TT owners that are running over 30 psi on a stock K04, but they also have massive intercoolers, w/m injection, different waste gate actuator springs and custom tunes to make it all work.

So, if the K04 turbos are proven to work at much higher boost, why not swap the RS6 turbos with TT turbos instead of trying to tweak turbine wheels etc.? Is the geometry different and intake/exhaust don't line up?

pressure is not always the same as flow.. some cars can make a lot more power with less pressure, but the flow is up there. All depending on intake/exhaust/engine volume and flow efficiencies. personally, I would never run 30psi on a K04. While pressure isnt always proportional to power.. it is to engine stress. I only run 14 on my tuned Noble, which is a V6 3.0L with twin GT28s

[V8weight]

I'm not sure that a carbon fiber hood would offer much in weight savings over the factory aluminum one.

[JSRS6]

It wouldn't. You MIGHT get 10-15 lbs savings.

[ttboost]

Yup. There are MUCH more cost effective ways to achieve weight savings...

[DALLAS_RS6]

Dave, the logs have been sent to you via email. Thanks!

[SteveKen]

Working with the same outer geometry turbo will never get you the bang for the buck you're after.

It's been alluded to above, but my intent on RS6 V3.0 if & when this happens is something like a set of TiAl R650s with V-band flanges and some elegant fabrication.

I can attest first hand that the manual transmission provides much more room for bigger turbos. I've also got a source where I can get the cores for fitment. I'm not sure if removing the bolt on flange and adding the v-band flange on the same plane will work. Luckily I've got an extra set of RS6 manifolds to experiment with.

So, to recap:

1. Manual tranmission, which I'd recommned whether upgrading or not, just from a pure reliability standpoint.

2. An aftermarket turbo with better performance (also most likely cheaper) than a stock set of Borg Warners.

[DALLAS_RS6]

Working with the same outer geometry turbo will never get you the bang for the buck you're after.

It's been alluded to above, but my intent on RS6 V3.0 if & when this happens is something like a set of TiAl R650s with V-band flanges and some elegant fabrication.

I can attest first hand that the manual transmission provides much more room for bigger turbos. I've also got a source where I can get the cores for fitment. I'm not sure if removing the bolt on flange and adding the v-band flange on the same plane will work. Luckily I've got an extra set of RS6 manifolds to experiment with.

So, to recap:

1. Manual tranmission, which I'd recommned whether upgrading or not, just from a pure reliability standpoint.

2. An aftermarket turbo with better performance (also most likely cheaper) than a stock set of Borg Warners.

Does anybody know the cost difference between rebuilding and upgrading my current trans vs. six speed conversion?

[ttboost]

Does anybody know the cost difference between rebuilding and upgrading my current trans vs. six speed conversion?

I think there are threads here detailing this? I seem to recall a $10k number for a 6speed conversion and somewhere between $4k and $6k for a rebuild and converter, or just $450 for the converter.

[Brav]

Does anybody know the cost difference between rebuilding and upgrading my current trans vs. six speed conversion?

I spoke with the guys at Raven MS about this when I dropped my car off there recently. Also got to see their 6SP RS6. Wow, lots more room around the tranny now! Anyway, It depends on how you go about it. I think they said parts can be had for around 6k or so. The total could be closer to 8k.

[JSRS6]

I spoke with the guys at Raven MS about this when I dropped my car off there recently. Also got to see their 6SP RS6. Wow, lots more room around the tranny now! Anyway, It depends on how you go about it. I think they said parts can be had for around 6k or so. The total could be closer to 8k.

I think if you do it yourself(which i will be doing as soon as its paid off), you can expect to pay 5-6K. If you have a shop do it with all the parts, 7-8K. If the shop has to fab their own stuff, 9-10K.

[V8weight]

I had the KW's installed free of charge in my car as well, as the DRC blew out 4 days after purchasing the car. It was covered under the 60 day dealership warranty. Me thinks there was some foul play by the dealership in the first place, my hypothesis is that they recharged the DRC for the test drive, to mask bad shocks.

[Brav]

Ahhh yes, Ducky. But I havent seen him on in ages?! Looks like he hasnt been on since Jan of last year. If you have his contact info, shoot me a PM if you don't mind