Doug’s 330i now has a TC Kline double adjustable coilover spring and damper suspension assembly to go along with a TC Kline front sway bar. The car also now has camber plates. All of the suspension mods allow for a massive amount of tunability, and Doug has worked hard to make the car driveable and quick, going to the limits of rebound in the rear, as well as camber and castor at the front.
Doug’s suspension tuning and driving abilities are obviously quite strong, as he won the ’08 California Divisional and National Solo championships, and has set track records at many of the local Phoenix circuits. However, while the car was definitely fun for me to drive, I personally was not a big fan of the increased castor in the car. The steering feel was ultra-light and almost overboosted, reducing the tactile feel of steering effort as load on the tires increased. It did, however, allow for wonderful economy of motion and efficiency, as I barely had to move the wheel to get the car to change direction. Again, though, I would’ve preferred a little more steering effort.
Grip from the massive Kumhos was almost comical, and in fact seemed to overwhelm the structural rigidity of the chassis at times. Despite some chassis-stiffening help from the immensely capable guys at Bimmerworld, the car seemed to literally twist with hard inputs on the throttle leaving slower corners, and the inside front tire was lifted a good foot to foot and half in the air! The feel inside the car was as though a giant rubber band were being stretched tight and then released, with all that energy causing the one-wheel wheelie! The resultant weight transfer to the rear helped put the power to the ground effectively, however, and it seemed to me that Guy Ankeny at ProParts USA, who did much of the shock valving, did his job well.
Doug didn’t mention too much about motor mods, although a custom lightweight header back exhaust and reflash resulted in 235 whp and 225 ft-lbs of torque. Those are some pretty decent numbers for what essentially is a stock motor, and Doug told me that he can routinely get wheelspin during autocross competition. While power was typical BMW in its delivery, which is to say almost perfectly linear, it wasn’t particularly strong, and with the grip this car developed, more power would have been welcome. Ultimately, this car is all about handling, and it performed that task with aplomb.
As is mandated by the all-encompassing rule book, Doug left the stock braking system on the car, which is exactly what we did with our KONI Challenge machine. Few braking systems out there, either stock or modified, provide the total feel of confidence in their ability to slow a car that BMW’s systems give. Even slowing from 150 mph repeatedly throughout a three-hour enduro in KONI competition was all in a day’s work for the stock binders on our 330, and I’m not sure that we ever truly reached their capacity to effectively slow the car or shed heat from the rotors. There has always been a sense of engineering integration in BMW braking systems that make them feel like a complete part of the vehicle. Sure enough, Doug’s car was able to shed energy predictably and capably, with my body being thrown against the stock three-point belt almost painfully. No sign of fade was felt throughout the driving sessions and overall braking was an impressive part of the machine, no doubt made even more so with the traction from the V710s.