Pull up a chair and read on if time allows or cut to the end for the summary of my experience and feedback on an APR remap to my B8 S4...
So I purchased a used S4 a month or two back. It's a stock '09 Avant with DSG transmission, aside from a simple Pipercross filter replacement.
I am delighted with the car itself - finish, drive etc however found the top end lacking and seemed to run out of puff at 5,000 RPM with a very noticeable drop off in pull and continued momentum. This often meant short shifting at 5K was the most effective way to ride the peak torque and power between around 3.3K and 5.5K
I'd read a lot of why this was - the supercharger has a bleed valve to allow any excess boost to be spent, though the Audi factory tune starts to open that valve at around 3.5K at wot, - hence why the top end of rev range seems flat, it simply dumps much of the boost pressure.
I started to research options to tackle this. First off I tried a tuning box, I liked the removable nature to allow me to easily return to stock for any warranty concerns, however whilst there was an improvement, it felt like there was still more gain to be had. Hence I decided a remap was the route to go ... choices were extremely limited due to challenges with accessing the ECU due to Audi software security steps. After much research and feedback I opted for APR as the vendor of choice. My personal reasoning was that the APR route allowed both a software and accompanying hardware option via remap and also pulley upgrade to supercharger plus they appear to have been established on this engine and ECU for some time with a large user base that seemed to share positive feedback.
Almost simultaneously, Awesome announced a great deal on their remap pricing with a 25% discount, though they were a fair distance from me and I was hesitant due to that consideration. This is where Evan at APR engaged and advised he could host me at their Milton Keynes facility to perform the remap on Awesomes behalf - thus reducing my travel to less than half. I was delighted and accepted without delay.
So it was that yesterday I arrived at APR's office. Being warmly greeted by Amanda (who kept me caffeine infused all morning), Andy whom was entrusted to perform the work on my car and Evan, who just seemed to breeze around the place and be cool ;-)
After a few hours of Andy's toiling, the car was finished. I had opted for the stage 2 upgrade - map and pulley replacement on the supercharger - I figured whilst the hood was up I might as well make the most of the time and get the best benefit I could (without an exhaust which I find just too pricey to justify presently). Whilst waiting Evan was kind enough to give me a thorough tour of their workshop and enjoy the aural delight of an R8 that was fitted with a supercharger ... sighs... one day when I don't need to lug a dog in the back...
I have to say after 24 hours to get acquainted, it's fantastic ! There is a marked increase in torque from around 2K which just keeps on pulling harder than before - funny enough my test drive I actually lifted off at just past 5K expecting the usual shift to be needed. Once I'd recalibrated myself - I let it scream and oish - it feels to fly. It still has the deceptive linear acceleration that I had loved just gobs more of it and a top end that's now just likely to get me in lots of trouble.
I'm still comparing and playing with different experiences of the car - but even with this limited early impression, I'd have to recommend this as a worthwhile upgrade. It's not cheap, though the gains are truly noticeable and it just makes the car an even better drive.
My thanks to John at Awesome for his patience and responsive nature to me plethora of questions prior to purchase.
Of course, also to Evan and team at APR - I felt like both I and the car were truly looked after and would heartily recommend them based upon this initial experience.
Now if you'll please excuse me, I have some local roads to go re-familiarize myself and my car with...