As promised, my dyno results below. My car is a March '06 completely STANDARD saloon with 21,800 miles. Service due in 3200 miles (last one at 15,500 miles). Runs were on optimax and 3rd gear to begin with and finally a couple in 4th gear but it seems it had got too hot by that stage with evidence of the ECU retarding the timing at the top end.
Thank you to Charlie at surrey rolling road who was very helpful and honest about the entire thing. He said mine was the first B7 RS4 he had done with more than 20k miles and so far also the first with figures reasonably close to manufacturer stated figures.
Just to clarify, the flywheel bhp figures are calculated using a 22% transmission loss. If you were to use a higher percentage as has often been mentioned for audi RS cars (anywhere between 24-30%), the flywheel bhp figures would look even more impressive. However, I'd mainly like to focus on the at-the-wheels figures as there won't be the issue of guessing the transmission losses.
1st graph - HP vs torque at the wheels
2nd graph - HP vs torque at the flywheel
3rd graph - AFR
4th graph - 3rd vs 4th gear comparison (red line = 4th gear, blue line = 3rd gear). By the time we got to do the 4th gear run, the car had become quite hot and it is likely the ECU retarded timing above 6,700 rpm where power drops off quite quickly (compared with the 3rd gear run which shows peak power pretty much bang on at 7,800 rpm). 4th gear WHP figure was 290.3 on this less than optimal run.
One other interesting thing to note was that below 5,500 rpm, there is quite a bit more torque/power in 4th gear. I wonder whether this is consistent with what had been discussed previously. I.e. that thethrottle opens 100% in gears 4-6 throughout the rpm range, as opposed to only 60% throttle opening below 5,500 rpm in gears 1-3.
