RS5 Dyno underpowered

[Rick_RS4]

ok so we know the rs models have been known to over claim their results but this is a bit much surely

http://translate.googleusercontent.com/ ... kmN-iwYu3Q

[HYFR]

uh oh

where's Sims and AutherPE

[Andyuk911]

I have a dyno credit with Surrey Rolling Road .. criteria, your car should be running on Super unleaded .. any takers ?

[RS6chris!]

Whats going on??? First our RS4,s not making stated power...now the latest flagship underpowered....Audi RS models are going to lose face shortly.......

[S2tuner]

RS6 TFSI put down the rated power without any problems

[HYFR]

and the 2.5TFSI

perhaps its just this 4.2NA FSI they have issues with, trying to squeeze out 100PS per 1000cc is quite difficult for Audi it seems without forced induction

[Andyuk911]

437 at low miles ... or Kms ..

http://www.rs6.com/showthread.php/19500 ... post202998


I started looking at RS5s .. but I feel they are over priced especially is you consider an R8 May 2008 car is less ....

[youry]

stopthe crap the RS5 is much closer to the announced power./tporiuqe figures. my dynoed at 1000 Km had 338hp and 335 Nm.... thsi engine is great and verrrrrrrrrrrrrrrrrry different than RS4 V8 engine which in average had 370hp on dynos (vs 420 announced)

[sonny]

stopthe crap the RS5 is much closer to the announced power./tporiuqe figures. my dynoed at 1000 Km had 338hp and 335 Nm.... thsi engine is great and verrrrrrrrrrrrrrrrrry different than RS4 V8 engine which in average had 370hp on dynos (vs 420 announced)

You put your new car on the dyno, are you mad? Engine not supposed to be red lined until the bedded in phase has been completed. 2500km irrc

So stick her on the dyno when it is bedded in and you may find that she will produce more power

[S2tuner]

OMG here comes the mechanical engineer/tuner again... So for you 338PS is good huh?

[P_G]

And you of course know that the ESP and quattro system between RS4 and RS5 is similar and not the same as used on the C6 RS6 and TT-RS so your point is.....

[youry]

sorry guys I mistyped. I meant 438 hp and not 338 of course.... during the three dyno runs, the values varied from 434, 436 and 438hp so not very heat sensitive.... not like RS4 V8 engine that when hot looses lots of power...

[P_G]

probably because of the larger engine bay and twin air intakes. The FSI V8 is shoehorned into the RS4 and suffers from heat soak

[ArthurPE]

the RS5 has a lower Cr 12.3 vs 12.5
yet makes the same torque 317 lb ft due to increased vol eff
T = Cr x (vol eff) x Vol / 4Pi
it makes more HP only due to a higher allowable rev
P = t x w (w = 2Pi x rev/sec)
it revs 7% higher and makes 7% more HP ~ 30

but look at the 1/4 mile trap speed/times, no real difference...
same weight

it would be illegal for Audi to over-rate the engine
the rating is done to an EU standard by an independent 3rd party

you guys worry too much