We recently had the opportunity to do a tune on a Audi RS4 V8.  This 2008 car is one of the cleanest rides we have seen.  Shockingly it has over 75,000 miles!  With a Milltek exhaust system, this customer wanted to get a little more juice to his super sedan.  The V8 in the RS4 shares the same 4.2L engine as the Q7 which revs to 8000rpm.  From the factory, the car comes with 420HP.  Using 91 octane and running on our Mustang AWD Dyno, we tend to have a 20-25% drivetrain loss.  That would put this cars stock wheel horsepower at around 315.  All cars always vary at whp and with high miles and low octane fuel, who knows how it would compare to a low mileage car on 93 octane.  But for testing reasons, what really matters is the before and after as well as the customers impressions.

The car baseline was 283whp and 261ft/lbs of torque.  The flashed car with and without sport was about 292whp and 267ft/lbs.  To the entry level enthusiast, this would appear as a a gain of 9whp and 6ft/lbs…  But look at the dyno graph below.  The car does not just have peak gains, but consistant almost 10 horsepower from 5000rpm to 8000rpm.  As the customer reviewed in the video, it pulls A LOT harder through the gears now!  Watch and listen.


About The Author

Dan Mermelstein - Co-Owner, Blogger, Porsche Enthusiast, VRTuned Marketing and Technical Support. Available to make your car faster!

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