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Had some time today so put our RS4 on our Dyno Dynamics dyno and it produced just 368bhp AFW and just over 300lb/ft torque - pretty poor.

Air intake was checked with VDRS at 34 and matched to the Dyno using the DD AIT probe.

We've a massive fan that sits at the front which generates more than enough air volume (we've had loads of far more powerful cars on the dyno, inc an F40 no problems), and the tyres weren't slipping on the rollers (pretty easy car to strap down)

So any comments on this figure or suggestions - also wondering what others have seen running stock maps on a dyno and which make of dyno was it.

GS

............flame suit on

Not at all surprising. We had one on a Dyno Dynamics machine which made around 305bhp at the flywheel (other cars on the day were producing their expected figures)!

Around the figures My RS4 was producing on a Dyno Dynamics Road, but on a Dastek road was 396bhp for the same car under same mechanical conditions.

Don't worry about it; if you are get a Racelogic box and do some 0-60 and 0-100 times and see if they match the quoted figures. If not, then talk to Audi but I suggest it probably will be there or thereabouts.

I'm sure this has been much discussed previously, but a DD set up in shoot out mode as per 'the manual' will assign a 20% drivetrain loss for your quattro - it appears globally anywhere between 25-30% is common assumption for our cars so take your pick.
As suggested standing starts against a proper timing box are probably a much more reliable heath check

More accurate results will come if you logged rolling times I.e 20-60 times as opposed to standing start times. It is very easy to lose .5s due to a bad get away or caring for your clutch..

they seem right to me?

as P G said, do some accurrately timed runs.

tis the only real world way to see if your car is underperforming...

rr results differ quite a bit it would seem.

From RR days I have attended in the past it was evident that NA engines gave out lower readings compared with manufacturers claims. 4WD on top of this gives significant further losses. On the other hand it seemed forced induction cars put out consistently accurate or better figures than manufacturers claims. The Mini Cooper S I ran put out 185bhp as stock with manufacturers claimed figures of 163bhp. On the other hand shed loads of 172 clio sports were only showing figueres in and around 140bhp. Yet after many blats on the private runway afterwards there was no seperating the cars.
Maybe some more technically minded people can back this theory / findings up?

And so it begins !!!

Probably cheaper to find someone with VagCom to measure your acceleration.

How do I transform vag-com data into readable data? what is tis?

where's the plot? what was the set-up?
what are the cf's? are they linear across the rpm band?
isn't >300 pretty much rated torque?
where are the raw, uncorrected numbers? the ONLY ones that are relevent

There is a facility in VagCom to do acceleration timing.

Rolling roads are very useful run pre/post a modification to measure it's worth perhaps?
Having come from ownership of a series of forced induction cars the RR picture there gets no easier

ArthurPE wrote:where's the plot? what was the set-up?
what are the cf's? are they linear across the rpm band?
isn't >300 pretty much rated torque?
where are the raw, uncorrected numbers? the ONLY ones that are relevent

wooah - 6 questions in one post - is that record ?

I'll post some graphs up when I get some time.

Had the intake manifold off today to check and its a clean as a whistle, also check the intake flaps and all working

GS