Here is a summary of the excellent report:
BMW Z4 GT3
First up: the Z4 GT3. My car was very similar to the Team Rahal Letterman Lanigan cars here in the American Le Mans GT (now Tudor) series, but ran in FIA’s GT3. A short, squat, flared, winged track weapon with a rockin’ 4.4-liter V-8 squeezed under the long carbon-fiber hood. No-lift paddle shifters, 8500-rpm redline, 515 horsepower – whoa. At 2750 pounds, it was more than 400 pounds lighter than my K-PAX Volvo S60. This Euro version had ABS and traction and stability control.
Dirk was not sure if the stability was on, and I’d say not much if any, because I got it pretty sideways when the Dunlop tires were cold. He warned me it would take some work to get them sticky with the 48-degree ambient temperature. The tire grip got better with each lap, and so did the handling behavior. As a racing driver, I focus on the negatives in a car and prioritize the issues, always looking to improve the speed. My first “negative” was that BMW had a very safe setup in the chassis, making the Z4 understeer a lot in the slow corners. This also could have been due to a tight differential.
Second was the high-rpm engine power: I could feel the restrictors doing their thing above eight grand — what a glorious bellow — but it was better to shift a little early, as this was a midrange (5000-8000 rpm) motor. Thus, the Z4 was not picky about gear choice. It had lots of lower-rev oomph, which also made it really good accelerating off the corner. Better than a Porsche, but not quite with our turbo Volvo, though with zero lag.
BMW M3 DTM