RS2 GT3071R dyno results

**4WheelDrifter** · 22 December 2007, 15:22

Originally posted by PapVas

i presume that ignition timing is also on the safe side on my remap due to the fuel quality concerns,or at least it is this why more fuel than needed is utilized while ignition timing is optimized,so at least there is no way of getting lean.
also at my graph there is a sudden drop in around 6000rpm which is ignition timing related as the guy on the dyno mentioned.He said it is probably due to fuel quality

What CR are you running? That will also dictate how much boost and advance you can safely run.

**AndyP** · 22 December 2007, 15:30

@Faheemo

Did you really run 460bhp on a std ABY intercooler?

**A80Avant** · 22 December 2007, 18:18

my CR is around 9:1

**Faheemo** · 23 December 2007, 11:53

Originally posted by AndyP

@Faheemo

Did you really run 460bhp on a std ABY intercooler?

If my Gtech calculation is correct , Yes.

the way my car was mapped, the intake air tempratures wher quite low.
Not sure if the intercooler was restricting the flow though.

**EspenW** · 23 December 2007, 20:52

Originally posted by PapVas

is the 25% include tyre losses as well?Since the dyno was done on a rototest hub dyno,then maybe the 25% is less?i dont know!

Numbers on a Rototest (or other hub dyno) will be higher than those generated on a rolling road, because there is no rolling resistance, and a lot less inertia (wheels and tires). Here is a vast collection of tests done by Rototest.
http://www.rri.se/index.php?DN=29
The (supposedly) 420hp B7 RS4 gets 330-340hp at the hubs.

**EspenW** · 23 December 2007, 21:04

Originally posted by Faheemo

Done in 3rd gear..

used equation: crank hp = (Gtech Hp +10 ) divided by 0.82

apparently this is the conversion used for calculating crank hp on 4wd cars using a gtech.
Is it correct ?

Good question. Remember that an S2 loses approx. 25hp to aero drag at that rpm in 3rd gear. In addition, losses to inertia are higher in 3rd gear than they would have been in 4th gear (or steady state as tested at the factory).
At what altitude did you perform the test? How about temperature, humidity and barometric pressure?
I have a Mr. Dyno performance tester that is very similar to the G-Tech, but it corrects to the SAE dyno correction standard (based on temp, altitude, etc).
In addition, it corrects for aerodynamic drag.
Due to low speed limits, I have done my tests in 2nd gear, getting approx 330hp to the wheels. Testing done at 5deg C. Raw, uncorrected (for athmospheric conditions)numbers are 355hp. I get 250hp in 1st gear, demonstrating how much power is lost to inertia (masses spin up faster the lower the gear), and the turbo not having enough time to spool. 3rd gear or 4th gear testing should yield higher numbers.
These kinds of performance testers are worth their weight in gold. I can get curves that overlay perfectly on back to back runs, so gains (or losses) from mods show up clearly.

**A80Avant** · 24 December 2007, 06:17

espen,that is nice to hear about the B7 and the crank hp to the rototest whp....
it means im about there...on the 400hp mark...on the 'supposedly' section though...

**Faheemo** · 24 December 2007, 13:46

Originally posted by EspenW

Good question. Remember that an S2 loses approx. 25hp to aero drag at that rpm in 3rd gear. In addition, losses to inertia are higher in 3rd gear than they would have been in 4th gear (or steady state as tested at the factory).
At what altitude did you perform the test? How about temperature, humidity and barometric pressure?
I have a Mr. Dyno performance tester that is very similar to the G-Tech, but it corrects to the SAE dyno correction standard (based on temp, altitude, etc).
In addition, it corrects for aerodynamic drag.
Due to low speed limits, I have done my tests in 2nd gear, getting approx 330hp to the wheels. Testing done at 5deg C. Raw, uncorrected (for athmospheric conditions)numbers are 355hp. I get 250hp in 1st gear, demonstrating how much power is lost to inertia (masses spin up faster the lower the gear), and the turbo not having enough time to spool. 3rd gear or 4th gear testing should yield higher numbers.
These kinds of performance testers are worth their weight in gold. I can get curves that overlay perfectly on back to back runs, so gains (or losses) from mods show up clearly.

I am at sea level - literally few meters above the sea level.
tempratures would have been in the 15 to 20 degree range.
cant remember the exact date , but was testing at nite - when no traffic around.
Only other factor could be the weight inputed into the gtech, I used 200kg more as i added my weight (100kg) + another 10kg for things that add additional weight like audio sound + 18 inch rims + bigger brakes + inverter and a laptop i run in the car + plus all the other small mods that add kg's.

Adding another 25hp for drag to 460 makes the hp figure unbelievable.

**Billman** · 24 December 2007, 16:09

According to roumours in Germany they never measured stock RS4 on the dyno with the stated 420 PS. Most of them have something arounf 400 PS.

**4WheelDrifter** · 24 December 2007, 16:26

That would be similar to the rumour that all stock RS2s are 300 bhp, not 315.

**Billman** · 24 December 2007, 18:48

I ve heard it for this about the RS2 for the first time. Dont know.

**EspenW** · 25 December 2007, 00:24

Originally posted by Billman

According to roumours in Germany they never measured stock RS4 on the dyno with the stated 420 PS. Most of them have something arounf 400 PS.

This is a topic for discussion over at RS246 as well as the US sites. The problem is that nobody (besides Audi) has pulled the engines and tested them to DIN standards on a proper engine dyno.
However, it is interesting to note that the RS4's pull 335-345ps at the hubs, while the R8 pulls 375ps at the hubs. Both are rated at 420ps at the flywheel.
I have seen B7 RS4's pull as little as 285hp at the wheels on Mustang type rolling roads.

**EspenW** · 25 December 2007, 00:29

Originally posted by 4WheelDrifter

That would be similar to the rumour that all stock RS2s are 300 bhp, not 315.

I've only heard that rumour once before, and I don't think it bears any truth.
Porsche supposedly bench tested every single RS2 engine for an hour to ensure that they produced the claimed 232Kw/316ps/310bhp.
Think about it, it is exceedingly easy to get more than 315hp from a standard ADU engine. Why would Porsche/Audi lie about the real output of the engine.
So called flywheel numbers generated from a session on a RR is in no way proof that the engine will not produce the claimed power when tested on an engine dyno to strict DIN procedures and standards.

**A80Avant** · 26 December 2007, 09:34

some vids...

Here are some 4th,5th gear pulls i did.I also tried a partial 6th gear but was interuppted by the small traffic.
It shows the surging on 4th gear and a bit in 5th gear.In 6th i get no surge.

Private Group Photo & Video Sharing

http://s117.photobucket.com/albums/o59/vasp3690/?action=view&current=6thgearpullhalf.flv