RS6 engine internals questions

[Whitbread]

Hello all, I'm a new guy around here, but not at all new to the Audi/VW world. I own a VAG performance shop in metro detroit and specialize in custom fabrication, custom engine/trans building, and engine swaps. However, I've never touched an RS6 before as they're such a rare beast and don't exist in my neck of the woods. That brings me here to ask the experts :hey:

I have a customer who will be shipping me a 37kmi RS6 with a bad transmission for a manual swap using the kit from a member here. I'm building him an 01e using a euro v6 tdi core with the built in oil pump, 4:1 center diff, etc. While I have everything out for the trans swap, he wants me to put a larger pair of turbo's on. I'm all for it except I don't know anything about the RS6 engine other than it's completely unique. What is the bottom end good to in terms of boost/power? Valve springs/cams need upgraded at any point? Anyone know what the stock injectors flow or approx how many hp they can support before hitting 95% duty cycle? If the engine will handle it, I'd love to put a pair of EFR6758's on it and have some scary fun.

Thank you guys very much for the help and knowledge. I've tried searching, but info on these awesome cars is thin at best.

[buster0984]

You'll have to either up grade the headers or swap the flange on the end as itswont mate with the efr turbos...probably knew that though ha!

I would say that the internals are pretty solid already. If you are only looking to build it to 650 or so you'll be fine. Actually I'm quite sure the motor has seen over 800 hp with stock internals and over 900 with forged rods/pistons. It's an alusil block so it was coated as well.

pm me of you want I have have a set of custom stainless headers and a set of 3071 turbos all new never mounted that I'm selling.

Sounds like exactly what I was doing! Good luck and PM me about the parts if you want.

[lswing]

Well, tuning and learning about the RS6 is a hobby of mine, so here's my 2 cents from the last few years.

At minimum, larger IC's and/or water meth. I'm running 10% more fuel than stock and IDC is around 80%. 85% max recommended but you know that can be exceeded.

To really make use of bigger turbos, and be safe, injectors, rails, pump also. Fitment can be a big issue too as there isn't much space to begin with. Someone just posted custom manifolds and bigger turbos, might want to jump on that.

[Whitbread]

I appreciate the feedback! I was planning on either re flanging the stock headers or building new if needed. All the fab stuff is of no concern, that's the easy part haha.

Buster, I found your for sale thread and I'm going to talk to the customer about the intercoolers. I was planning on building new units with Bell cores, but as complex as the end tanks look, I'd much rather buy the Wagner ones from you and save myself a ton of time. I'd do your headers and turbos too, but I'm pretty stuck on EFR units (which are slightly differently shaped than garretts). I've used quite a few now with amazing results. By far my favorite turbos currently available. Good to know the internals are stout enough for 650whp with sensible tuning. Saves me alot of work there.

Lswing, thanks for the injector/fuel system data. I'm a dealer for fuelab so getting a larger pump will be easy. Does anyone sell rails and injectors for these? Or have recommendation for aftermarket ones that drop in with minimal mods?



Here's some random pics of semi recent projects, everyone loves car porn.

LS7 catless downpipe
http://i702.photobucket.com/albums/ww29/mrwhitbread/2013-04-22135040_zpsdf3bc082.jpg (http://s702.photobucket.com/user/mrwhitbread/media/2013-04-22135040_zpsdf3bc082.jpg.html)

05 cummins twins, he351 and S482.
http://i702.photobucket.com/albums/ww29/mrwhitbread/2012-05-16010404.jpg (http://s702.photobucket.com/user/mrwhitbread/media/2012-05-16010404.jpg.html)

Custom billet 304ss cnc turbo discharge flange
http://i702.photobucket.com/albums/ww29/mrwhitbread/Snapbucket/21638CFF-orig_zps94e873de.jpg (http://s702.photobucket.com/user/mrwhitbread/media/Snapbucket/21638CFF-orig_zps94e873de.jpg.html)

Built chassis and all fab work on this le mans prototype car
http://i702.photobucket.com/albums/ww29/mrwhitbread/Snapbucket/146BC67B-orig_zps73f692a7.jpg (http://s702.photobucket.com/user/mrwhitbread/media/Snapbucket/146BC67B-orig_zps73f692a7.jpg.html)

90% finished race cage
http://i702.photobucket.com/albums/ww29/mrwhitbread/Snapbucket/94BB0AEE-orig_zps5acd183b.jpg (http://s702.photobucket.com/user/mrwhitbread/media/Snapbucket/94BB0AEE-orig_zps5acd183b.jpg.html)

[G2]

Super nice looking work there! Few supporting ideas and thoughts on that project:

As a fellow pro wrench, it can be a challenge to evaluate someones' machinery-- It may have low miles and "had all maintenance done, etc, etc", but the reality goes much deeper. To keep this suscinct, our approach for vastly increasing power would entail a minor physical inspection of valve train, cylinders (leak down and boroscope), oil pressures, oil (UOA) testing, and maybe a look-see at a couple bearing surfaces. Any combination of these items would help gain valuable insights.

We have a S5 4.2 FSI, S6 and RS6 in the shop and a S4 V8 coming in later next week. Regarding fuel rails: From a quick visual the RS6 rails are much, much larger. So much that we plan on heat wrapping them due to low fuel flow (but then again it is a return type system, so that's good) and heat soaking. A couple of gauges could monitor if 650+hp is sustainable or 4 gas on a dyno to check IDC vs AFR.

Now if there was a way we could steal the Fuel Cooler from the 928S sitting outside...(uses the A/C system for a real chill down). In terms of fuel flow, the fuel filter makes me wonder-- it's small, so are the inlet-outlets. Doesn't even use Banjo bolts like Audi's of this age normally use. I may address this "engineering compromise" at some point, pending further research and testing.

My thoughts are that the OE air intake will be rather limiting at much higher power levels. The filters are quite small. I put in K/N's recently and was fairly sure the car responded noticeably better.

Oil is of course important. We continually see OE spec oils not holding up, even in daily unmodified drivers- BMW, MB, Audi, Mini and so on. Some are "worse" than others. Thankfully the RS6 has a robust oil cooler to reduce burn off (NOACK). However, we always use AMSOIL lubes with high additives for the older and performance cars. The S5, despite being newer, low miles, is getting changed over today. The owner drives it hard and doesn't want to prematurely deal with timing chain issues. At anyrate, we'd never use a OE spec oil in the RS6. I would consider it a dis-service in anything other than a stock daily driver using shorter drain interval. And that would still make me cringe....

We're still newer to the RS6 (but not Audi's), still much to learn. But personally owning one allows complete immersion and taking the time needed to address our point of view, concerns and methods. Those years of engineering experience may also pay off for a car so complicated.

Keep us posted how the high power C5 comes along. Gotta head to the shop and make a S5 go faster...

[Whitbread]

Thanks G2! I get my hands into just about everything :incar:. I just started swapping a 03 W8 6MT passat sedan to a built 2.0L 2004 TDI motor. Should be about ~275whp/450wtq and 40 mpg. Have a pile of go fast parts and the donor almost gutted. Hoping to finish around christmas. The W8 will find it's way into a Razor (http://superlitecars.com/razor/gallery-razor/) with a fwd 01E behind it. That will be the stupid mobile!

A full once over of the whole car/engine is planned. That was the original thought with pulling the engine for the manual swap, then I said "while it's out, you might as well put bigger turbo's on there" and it snowballed as usual.

Ok, so the fuel rails are probably fine, just need larger injectors with a fuel line/filter/pump upgrade. Easy enough.

I see Apikol (http://www.apikol.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/r/s/rs6_intake_zoom_23.jpg) has a hot air intake of sorts, looking at how tight everything is, I don't see many other options without the car in front of me. Think this would be the best compromise for a simple, higher flowing system? I'd use amsoil or aem dry filters though, not a giant fan of K&N. Can the Maf's be tuned out/deleted on the RS6's? I do alot of work with VW TDI's and that's the first thing I have my tuner do, makes things simpler and cleaner.

Schaeffer 5w-50 or 20W-50 is the only thing that enters my engines. I'm with you, OE spec oils belong in lawnmowers.

Depending on how this project turns out, I just might have to buy the next one I find with a blown auto. I've always liked s2/rs4/rs6's. 5 cars isn't enough for a single guy with no kids, need at least 7 haha!

[4everRS]

You guys obviously have a lot of experience. Very impressive and I must say, I'm a bit envious of the skills you have.

In regards to the intake, I've data logged different filters in the place of the stockers. There was absolutely no difference in measured mass air flow. Speaking of mass air flow, I believe the Bosch motortonics system uses maf readings to help determine fueling.

I don't know about a different intake. I do know that while watching the car on a chassis dyno, you can see the stock airbox "suck" down and the top carbon area become slightly convex.

[Styhl]

Hey y'all I'm going to be getting my rs6 real soon and I use Shaeffer oil in my 2.8 N/A Passat. Is this an okay oil to use in my rs6 motor, or will it cause problems for the turbos or anything? I assume its okay I just know its Temperature handling profile is a bit different than conventional style oils and I didn't know if this could harm the required cooling profile needed for the turbo oiling system. and is the 5w oil okay?

[hahnmgh63]

Audi's requirement for the RS6 is VAG 505.01, make sure the oil your using meets that spec (it's a TDI oil spec actually). The only oils I know of that meet the spec are full synthetics, no conventional oils here. Almost all are 5w-40 oils but I think they're maybe a 0w-40 and/or 5w-50 that might meet it too.

[CBeau]

http://i702.photobucket.com/albums/ww29/mrwhitbread/Snapbucket/146BC67B-orig_zps73f692a7.jpg (http://s702.photobucket.com/user/mrwhitbread/media/Snapbucket/146BC67B-orig_zps73f692a7.jpg.html)

What kind LMP car is that? What is whoever using it for?