RS4 B5 4.2 V8 Single turbo trackday/timeattack

[Mazmip]

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[a4kamila6]

well damn, good luck! Didnt know c4's had 4.2's, gotta look it up.

[landfill]

Wow I wish more people stateside did some of these crazy big power
audi builds like you guys in Europe are doing. Here in the states if it's
domestic or JDM no problem. Most people look at me funny when I tell
them I build euro cars.

[landfill]

Only in europe they had the option of getting the 4.2 in the urs6.
The s6+ was a quattro gmbh 97 only car that was only available
with the 4.2L v8. North America only had the urs6 with the AAN
although some s6+ cars do exist up in Canada.

[BITRBO]

dude, this may be the coolest project I've seen in a long time.

Keep us posted OP

[NOTORIOUS VR]

Not sure how I feel about the V8 taking the 2.7T's place, but I can see why you're doing it. Didn't consider a different turbo for the 2.7T to hit your power goal or are you worried about the power band?

Although if you don't mind me asking, can we see some more info about the 2.7 w/ the 9180? It's a turbo that I thought would be a great combo for the 2.7T personally.

Can you give a quick run down on the 2.7T engine specifics (especially top end, heads/cams, RPM limit) and if possible a dyno chart from the 9180 on kill?

Thanks!

[rguil]

What did the 9180 spool like?

[blitz2190]

What did the 9180 spool like?

very interested in this as well, I'm looking at going this exact route this tax season, and want to match the pulley on my eaton m90 for the 9180 curve. I just built the bottom end and hoping to have it broken in by then. Also curious about that intercooler on the front and who tuned it, was it you guys or was it a third party?

[Mazmip]

The main reason for the 4.2 is to get wider powerband and to have more torque early. With the 2,7 setup the car wasn't able to accelerate in 6th gear on speedweekend so we drove the last 600meters on revlimiter in 5th gear.

Engine spec 2,7
-Main girdle plate
-Arp studs main and topp
-eagle h-beam rod
-supertech piston +0,5
-ported 2,7 heads
-+1 mm eksaust valves (rest of the head stock)
-ported rs4 inntake manifold
-And we were running hydraulikk camshaft adjuster controlled by Autronic sm4. With god help from Ian from Autronic in Australia and Kai at KRB Trading.
We are using Kai at KRB-Trading for tuning the cars.
The intercooer worked out fine. In the log file the intake temp stays between 35-40 degrees (c) on drag and small track event. We only had issues when we pushed the car for several laps on the longer tracks her in Norway.

After some test the revlimiter was set to 7800

[Mazmip]

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[getslideways]

Congrats on how far you have already come! Looking forward to following this as you chase the WR. Do you have any videos of the car in action on the snow or on the track?

[S4James]

Only in europe they had the option of getting the 4.2 in the urs6.
The s6+ was a quattro gmbh 97 only car that was only available
with the 4.2L v8. North America only had the urs6 with the AAN
although some s6+ cars do exist up in Canada.

Freind of mine had one.

[NOTORIOUS VR]

The main reason for the 4.2 is to get wider powerband and to have more torque early. With the 2,7 setup the car wasn't able to accelerate in 6th gear on speedweekend so we drove the last 600meters on revlimiter in 5th gear.

Engine spec 2,7
-Main girdle plate
-Arp studs main and topp
-eagle h-beam rod
-supertech piston +0,5
-ported 2,7 heads
-+1 mm eksaust valves (rest of the head stock)
-ported rs4 inntake manifold
-And we were running hydraulikk camshaft adjuster controlled by Autronic sm4. With god help from Ian from Autronic in Australia and Kai at KRB Trading.
We are using Kai at KRB-Trading for tuning the cars.
The intercooer worked out fine. In the log file the intake temp stays between 35-40 degrees (c) on drag and small track event. We only had issues when we pushed the car for several laps on the longer tracks her in Norway.

After some test the revlimiter was set to 7800

Thanks for the info...

Looks like you could have used some help with camshafts and/or something else, that mid-range power band/TQ is really, really soft? I'm actually very surprised of that dyno with the 9180 to be honest.

For reference this is a BMW 3.2L S52 (US) that I tuned with a 9180 (1.45 housing) on E98 (don't mind the squiggly lines - we had really bad wheel spin):

Approx 25-26 psi:

[redline380]

Very interested on detailed 4.2 motor build and parts that are going into it

[pee quu]

jebus. cant wait to see the motor

[Mazmip]

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[Mazmip]

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[NOTORIOUS VR]

Yes some camshaft would have helped. Taking the v6 engine build up i wasn't sure if wanted to push so muth more out of it 998wnm is approximately 1170nm in engine. But in the long run this is a plan for something bigger :-) Iam driving in Gatebil Extreme series her in Norway where thers all kinde of monster are participating. I hade a BMW E34 that i just sold to build a fully tubular frame B4 with a mid engine and rwd. The plan is to have a 4,2T in it so that some of the reason of the 4,2 bulid in my RS4 to test it out. We are going to start building the new car closer to summer 2017 and the goal is to have it done to the racing season 2018.

Here is a link to Speedhunters with spotlight on my E34 as i just sold a few months ago http://www.speedhunters.com/2016/08/...n-extreme-e34/

What a fantastic E34! I saw it randomly on the internet some time ago. Very nicely done!

I'm excited to see the progress on the turbo 4.2L!

[james 408]

Sweet, right in KRB's wheelhouse... http://www.speedhunters.com/2013/07/reinventing-an-icon-krbs-829whp-lotus-lives/
Kinda hybridizes their audi/lotus builds.

RE 2.7: Not surprised there were cooling issues after a few laps and turbo lag issues, also see the block was reinforced. There any footage online from it on a road course? Would be curious to see exactly how that went

[blitz2190]

so what is the actual intercooler, do you have a link or is it a custom one?

[Mazmip]

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[james 408]

Sweet, can't have an ice racing event without a shirtless swede wearing a helmet taking a dip in the icewater.

Any onboard from the curvy section/a road course by chance on the 2.7?

Intercooler/Radiator interface: I did some research on it a long time ago, when stacking coolers, they say keep them close, but not touching, and seal the edges so airflow can't escape out (maximize pressure differential between the front of the first cooler and out the back of the last cooler. Might be worth looking into the seal of the radiator flaps to the bumper as well. I noticed yours looks like the fins are designed to let air flow towards one side of the radiator but not the other, not sure but this might be reducing airflow through the radiator? who knows. Maybe you did this to allow air to flow towards the airbox, dunno. Opening the back of the engine bay with gapped fenders is another way to increase the pressure differential. Regardless I think we're just talking fractional improvements...
Guess you'll be doing rear mounted radiator anyway on your full build. You're doing more the time attack class?

[Racin2redline]

holy hell this thing is bad ass

Sent from my SM-G900P using Tapatalk

[ElementR]

Sweet, can't have an ice racing event without a shirtless swede wearing a helmet taking a dip in the icewater.

Any onboard from the curvy section/a road course by chance on the 2.7?

Intercooler/Radiator interface: I did some research on it a long time ago, when stacking coolers, they say keep them close, but not touching, and seal the edges so airflow can't escape out (maximize pressure differential between the front of the first cooler and out the back of the last cooler. Might be worth looking into the seal of the radiator flaps to the bumper as well. I noticed yours looks like the fins are designed to let air flow towards one side of the radiator but not the other, not sure but this might be reducing airflow through the radiator? who knows. Maybe you did this to allow air to flow towards the airbox, dunno. Opening the back of the engine bay with gapped fenders is another way to increase the pressure differential. Regardless I think we're just talking fractional improvements...
Guess you'll be doing rear mounted radiator anyway on your full build. You're doing more the time attack class?

Biggest problem as he noted is space between radiator and engine which is already very tight on the stock arrangement. I develop powertrain cooling systems at a major auto OEM and have been in this field for (hard to believe) nearly 20 years. The relationship between airflow and distance between radiator and engine (when nearby relatively speaking) is airflow varies by distance to the power of 4 so it's a huge detriment to move the radiator too close to the engine.

Without a proper sealing package, airflow will tend to bypass the FMIC and head into the radiator (path of least resistance), but here it's fighting the engine closely behind. Audi didn't set this package up with much room for improvement unfortunately. As with most underhood envrionments these days, we try to fit 10 lbs of sand in a 5 lb bag.

True that adding vents to fenders will help draw air through.

But all of this is in Norway... isn't the average ambient around 0 deg?

[DieselElectric]

I'm curious to see the rear mount radiator setup (along with the rest of the car). It's something I've always been curious about but never really looked into.

Badass build though, wish I clicked the title earlier!

[landfill]

^^^If you go on s2forum alot of the guys building old 20v 5cylinder rally cars
are using the rear mounted radiator. I also heard the early s1 audi rally cars used
a rear mounted radiator as well.

[james 408]

good info, i'd make a couple counter/rounding off points:

1) distance to engine is important due to airflow reasons and additionally longer cooling pipes = more coolant and more cooling. all good points.
what i'd round off the argument is saying:
a) the radiator isn't moved; you've just stacked a core on it with the FMIC. the problem with this is heating up fmic air into the radiator. Distance BETWEEN the coolers would be adventageous, but not only is that not possible, but it's actually detrimental according to some race teams. What they are arguing is that it's better to allow the air to be heated, leave the coolers close, and prevent the air from escaping; in other words, the air pressure differential between the front and back of the cores is more important.

2) rear mounted radiator is common in motorsports applications, PARTICULARLY in very short racing formats. For endurance racing, you'd more likely put the intercooler back there, and leave the radiator up front -- especially when considering pressure drop on a mid-engined car.

[ElementR]

I gathered from comments and pics above that the core support was cut and radiator moved rearward. Yes, FMIC or any heat exchanger in front of the radiator is detrimental from airflow and heat rejection point of view. It's best to minimize depth between heat exchangers and seal the gap. With dissimilar sized (face area) cores, this is challenging. In a perfect world, the opening at the front of the car would match the size of the radiator/FMIC both of which would be perfectly matched in size and sealed to one another, there would be significant space (several inches) from rear of radiator to engine along with plenty of opportunity for the air to escape the underhood... but then you'd have the Aero guys screaming for drag impacts. I oversimplified things a little ... reality is far more complex.

[james 408]

ah, I misread which gap he was referring to. And thanks for sharing the info .

[rockcandy]

What details can you provide on the 4.2 build??

[Mazmip]

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[jibberjive]

Killer build(s). Sub'd and following, cheers.

[Mazmip]

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[themadscientist]

Finally all the fabrication on the chassi is done of to the paint shop tomorrow

Motherofgod.jpeg

How much did it cost to get the block nikasil lined?

[Mazmip]

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[NOTORIOUS VR]

The nikasil treatment cost 20000,- nok that's about 2400usd.

Ouch, did you consider to install steel sleeves instead of doing the lining?

[RS2]

very nice! i think i saw your car at gatebil 2012? :)

[blitz2190]

quick question, why not an rs6 block, or even the 40v c5 4.2 block?

[NOTORIOUS VR]

quick question, why not an rs6 block, or even the 40v c5 4.2 block?

RS6 block is totally different and then you have the difficulty of mating a manual transmission (has a very large bell hosing pattern on the block for the automatic). Also very rare therefore expensive.

[Mazmip]

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