rs2 on the rollers

[rallyejames]

Hello guys......had an oppertunity to put the rs2 on the rollers yesturday,but came away felling a little dissapointed
the car has had a generic re map,,cats removed and miltek fitted and boost peaking at 1.8 bar.
How do these figures look to you? didnt really know what to expect to be honest...but a little more would have been nice.

Engine power(measured) 356.7hp @ 95mph/6074 1/min
Wheel power(measured) 301.9hp @ 95mph/6074 1/min
power losses(measured) 54.8hp @ 95mph/6074 1/min

Engine power(corrected) 343.8hp @ 95mph/6074 1/min
Torque(corrected) 397 lbs/ft @ 4247 1/min (engine)

i will try to post the graph asap....very uneven power curve....and torque peaks at 4247 rpm and then just drops to 200 lbs/ft @ 7500 rpm?????

What do you think??????? thanks James

[Fat Audi 80]

345 bhp and 400ftlbs is bloody storming!! Standard is 315bhp and 300ftlbs IIRC..

You may see 360bhp with the high boost chips but no more with that set up.

Need to see the graph to gauge driveability.

You should be very happy!

Cheers,

Steve.

[UrS4boy]

That is similar to my RS2'd UrS4 with an MRC chip set. See the second (lower) graph in this post:

http://forums.audiworld.com/s4s6/msgs/111199.phtml

You can get a *bit* more from the RS2 turbo, but not much.

BTW, I went back to the 1.9 bar WG spring - but with the spring perch turned all the way up.

[Bram]

Hello guys......had an oppertunity to put the rs2 on the rollers yesturday,but came away felling a little dissapointed
the car has had a generic re map,,cats removed and miltek fitted and boost peaking at 1.8 bar.
How do these figures look to you? didnt really know what to expect to be honest...but a little more would have been nice.

Engine power(measured) 356.7hp @ 95mph/6074 1/min
Wheel power(measured) 301.9hp @ 95mph/6074 1/min
power losses(measured) 54.8hp @ 95mph/6074 1/min

Engine power(corrected) 343.8hp @ 95mph/6074 1/min
Torque(corrected) 397 lbs/ft @ 4247 1/min (engine)

i will try to post the graph asap....very uneven power curve....and torque peaks at 4247 rpm and then just drops to 200 lbs/ft @ 7500 rpm?????

What do you think??????? thanks James

Did you perform the RR session in 3th or 4th gear? It should always be in 4th gear on a turbo engine in order to have the turbo spool earlier and to it's full boost profile.

[Rusty]

Those are good figures. If you want to look for more and haven't already done so, give the car a service with new plugs, check the dump valve isn't leaking and get the inlet pressure tested. Peak boost is not as important for power as boost at about 6500. Run was in 3rd so I guess it was a Dyno Dynamics roller with no run down losses? You'll more than likely find some more ponies with a little tlc, I found 25 from a boost leak. Did you get the AFRs measured, they should be about 12 from 4k onwards. Any lower (like 10) and you've got a leak IME

[nip]

who remaped it?

[EspenW]

Run was in 3rd so I guess it was a Dyno Dynamics roller with no run down losses? You'll more than likely find some more ponies with a little tlc, I found 25 from a boost leak. Did you get the AFRs measured, they should be about 12 from 4k onwards. Any lower (like 10) and you've got a leak IME

300whp would mean a LOT more than 350 crank if measured on a Dyno Dynamics. B7 RS4's pull 280whp on the DD.
I am sure the pull was made on a Dastek dyno, they usually show OK estimated crank numbers, but their whp numbers are too high.
If this car really pulled 302 at the wheels, real crank power would be in the 375 to 400hp range.
15% drivetrain loss is too low on a medium powered quattro. Dastek just adds the unloaded coastdown losses, which will be much lower than real losses since they are measured w/o load.

[GazzaG60]

looks good.

high torque is down to a small turbo witg lots of boost. th e peak will be in the midrange and expect it to drop off. on the road this will be quick. bigger turbos make better dyno queens.

look for afs in the 11-12 area like andy said. 10's id say is either a boost issue or a mapping deficiency.

[EspenW]

That is similar to my RS2'd UrS4 with an MRC chip set. See the second (lower) graph in this post:

http://forums.audiworld.com/s4s6/msgs/111199.phtml

You can get a *bit* more from the RS2 turbo, but not much.

Dave, 288hp from that Dyno Dynamics run is not bad at all. These dynos are way strict (depending on operator setup, of course).
B7 RS4s usually pull around 280whp on these, so in case this particular DD isnt calibrated to read high, 288whp should be more than 360chp

[Ross]

Just to add to the thoughts already expressed - it's a damn good power run, that torque figure is spot on, but the power is clearly down on expectation but only by about 15-20hp for that setup! The 302 @ the wheels is very good, generally it seems the quattro is about 22% on drivetrain (right?), which would put a conservative corrected figure (we'll say 20% drivetrain loss) at 362hp.

[S2central.net]

Yep ... If that 302bhp ATW is accurate, then remember that a nicely upgraded S2 on K24 turbo runs about 210-220bhp ATW - so thats a mighty hike. I wouldn't get distracted by rolling road loss estimates. ATW is what matters

[Al Wyn]

who remaped it?

MRC

[Jamo]

Looks good to me 302 whp = what 375 crank HP?

Stonking without a 3" downpipe as well.

[Rusty]

300whp would mean a LOT more than 350 crank if measured on a Dyno Dynamics. B7 RS4's pull 280whp on the DD.
I am sure the pull was made on a Dastek dyno, they usually show OK estimated crank numbers, but their whp numbers are too high.
If this car really pulled 302 at the wheels, real crank power would be in the 375 to 400hp range.
15% drivetrain loss is too low on a medium powered quattro. Dastek just adds the unloaded coastdown losses, which will be much lower than real losses since they are measured w/o load.

Oops, missed that... My RR chap uses Dastek and his figures are pretty believable although they're done in 4th. 50bhp losses are very low for 6000+rpm, I'd expect higher based on my car. 3rd gear might have been the issue.

[EspenW]

The thing to keep in mind is that whp numbers will vary wildly between different types of dynos as well.
Example: The R35 GTR pulls appprox. 460hp at the hubs on the Rototest (the only real measurement besides an engine dyno that I trust). Note that readings at the hubs will be much higher than readings at the wheels.
The GTR pulls 458hp at the wheels on the Dastek dyno (the one I suspect has been used above), in other words a whp reading as high as the true at the hubs reading. Clearly wrong.
The GTR pulls 410-420 true whp on a proper loading dyno like the Mustang Dyno.
Moral of the story is that not even whp numbers are absolute, and Dastek rollers (along with Dynojet) produce whp numbers that are artificially high.