2007 Audi A4 Quattro - Proven

Like its predecessor, VAG's 2.0T motor has put tuners in a frenzy. Boasting 30 percent more power than the successful 1.8T, the 2.0T pumps out 200 hp, making it a great powerplant to start with. Our friends at APR in Alabama have been all over it, and recently we tested some of the company's upgrades.

APR's intake and software system is a good place to start. For $978, you get quite a bang (the good kind). We used a 2007 Audi A4 Quattro with a six-speed automatic transmission that's barely shifted through 1000 miles of driving. Our baseline runs were performed at Imagine Auto, a Porsche specialty tuner based out of Lenexa, Kansas. IA's Mustang MD Dynamometer was used in all-wheel-drive mode (AWHP), which IA states is around five percent more conservative than its wheel-hp figures in two-wheel drive mode. It's also known to spit out conservative readings. A stock 146-AWHP pull made us believe it.

Thanks to the slush-box, quarter-mile acceleration testing would be easy, which IA's dyno has the ability to do. We took advantage of this feature and posted a 16.1-second quarter at 85 mph for a baseline reading. We were anxious for an improvement.

The APR intake and software, was installed at Bob Hindson Racing, a Porsche, Audi and VW specialty shop also in the Kansas City area. BHR loaded up APR's 91-octane, 93-octane and 100-octane tuning programs, as well as a fourth program that resets the stock software if needed. Each of the first three programs provides the same one-bar (14.7 psi) boost, but the higher the octane program, the more aggressive the tuning. Program selection is done by using the cruise control button and noting how many times the 'check engine' light flashes in five-second intervals.

Our initial drive using the 91-octane program provided evidence of a tremendous gain in torque and top end power. The new intake also provides the whooshing sound from the turbo diverter valve. On the stock car, this is largely inaudible.

Back at Imagine Auto, a third-gear pull registering 182 AWHP and 206 lb-ft of torque confirmed driving impressions. Peak gains already showed a 30- to 47-hp increase across the board, with a peak torque gain of 77 lb-ft at 2400 rpm. In the quarter-mile test, this was good for 15.6 seconds at 89 mph. A half-second gain here may not sound a lot, but it translates into an advantage of five car lengths at the finish line.

At this time, the fuel tank was a quarter-full of 92 octane. We added a couple gallons of 100 octane unleaded race fuel to bring the effective octane above 93, and hit the cruise control switch to load the corresponding program. After a 15-minute drive against the dyno load, we felt the software was ready for testing. Peak power rose to 196 AWHP with a nasty 223 lb-ft of torque; a 40- to 60-hp gain from 2950 rpm up to the redline. Our quarter-mile acceleration improved to 15.2 seconds at 89 mph. We're now crossing that finish line about 10 car lengths ahead.