what is the actual % loss from crank to wheel?

[speedtrapped]

So post dyno, just curious I was told originally that from crank to awd lose 20%, but add tip and likely lose 25%, anyone have definitive answer on this?

[skribe]

Never been able to find a definitive answer on this either. Anyone? Conventional wisdom is like you said, tiptronic AWD Audi = 25%.

Makes me want to disconnect my front drive axles sometimes.

[V8weight]

Never been able to find a definitive answer on this either. Anyone? Conventional wisdom is like you said, tiptronic AWD Audi = 25%.

Makes me want to disconnect my front drive axles sometimes.

Ya, I usually figure 25% loss. It varies by dyno though.

[JSRS6]

That's the % I have entered in my dynolicious app for iPhone ;-).

[ben916]

I haven't found this answer so I will ask it now:

Aside from the fatherland, has ANYONE performed a Engine dyno (engine/turbo/ecu/intercooler/etc) on the RS6 motor?

[ntrcptr]

25% seems way too high.. perhaps on a mustang dyno; i'd say 15-18% -using the dynapack dynomometer

[vr430]

Everyone is going to be different. Back in my EVO days, 5 identical stock EVO's running on a dyno on the same day produced results anywhere from 190 to 220HP. You would have to peg each car separately - on a dyno and on a stand to get true numbers. However, we used 25% loss as a rule of thumb. But then why would anyone care about crank HP? It's what at the wheels that matters.

[JSRS6]

Yes, but our tc's are built to handle I think 550 coming off the crank, so we want to be safe in that respect to prolong the life of the tc.

[Hy Octane]

25% is about right considering its AWD and an automatic..

[ben916]

... But then why would anyone care about crank HP? It's what at the wheels that matters.

TRUE and I agree on what is at the wheels... but there was some controversy early on in the life of some Audi's (not necessarily the RS6) of the factory fudging the numbers of 340hp/400hp/450hp/etc whether or not there was a true HP rating or if it was pure optimal conditions in which a said model line/engine actually put down the HP numbers advertised.

Case in point is the RS5 - advertised with 450HP, IIRC...

[vr430]

Yes, but our tc's are built to handle I think 550 coming off the crank, so we want to be safe in that respect to prolong the life of the tc.

Wow! Audi does not leave much room for error! Just use 25% and you'll be on the safe side of things.

Curious that MTM's most expensive upgrade brings HP to 568 without touching TC.

[vr430]

Aside from the fatherland, has ANYONE performed a Engine dyno (engine/turbo/ecu/intercooler/etc) on the RS6 motor?

Yeah, it would be interesting to see if someone had indeed tested RS6 motor on the bench.

...controversy early on in the life of some Audi's (not necessarily the RS6) of the factory fudging the numbers of 340hp/400hp/450hp...

Does Audi report numbers that are more or less then observed? Funny how in Japan, at least a while back, no new car could be sold with more than reported 300hp. So even the mighty GT-R spec was listed at 299HP. Yeah, right!

[ttboost]

I seem to recall a stock RS6 making between 300-320 awhp on a Mustang dyno. If the 450hp is correct or even close, that's a 29% loss....not really unheard of for these german slush boxes... I've seen 996 turbo tips dyno even worse. I think 25% is conservative. Use real world numbers instead, not dyno numbers...you'll be less disappointed...

[speedtrapped]

Ben funny you should say that about fudged #'s my audi tech tells me on my S8 that Audi purposely underestimates HP for emissions purposes in US....not sure if true, he thinks my S8 puts out alot more then 450hp(stock)

[marklar182]

Yeah, it would be interesting to see if someone had indeed tested RS6 motor on the bench.

I believe I read that the BCY motor made way more power on the engine dyno. Limited cooling and the cramped space under the hood required major detuning.

[peiserg]

mine made 340 awhp with about 7000 miles on the clock with 91 octane temps 100ish

[ttboost]

mine made 340 awhp with about 7000 miles on the clock with 91 octane temps 100ish

Optimistic dyno?... and that would be 25%...

[sallyh]

Hi all

so, has anyone actually put their beloved V8 or V10 on the dyno? I had an offer a while back to put my V10 on the dyno for the development of a tune for the RS4 and ended up saying no as the risks were too high for my car. But, that said, I'd absolutely love to verify the 572 bhp (rounded off to 580) for the V10. In a real world context it feels like it is, like it accelerates very fast for its weight, but has anyone actually tested it? "The World's most Powerful Station Wagon"? is it true?