In my previous M3, I enjoyed using the BMW GT adjustable front splitter mentioned earlier (and seen on BMW M3 Lightweights) for track days-and it really worked. But even though the 4.0-in. extension could be fully retracted in a matter of seconds, I found myself bottoming out quite frequently on the street. It was the additional 1.0-in. drop from the popular plastic L-shaped lip extensions that contributed to this nightmare. In addition, although it was very functional, the O.E. BMW splitter was heavy, not to mention very expensive (over $1,100). This was due to all of the expensive bolts and the much-needed brackets for the kit.
This time I wanted something that would be adjustable, functional and streetable. It was an easy choice to go with Racing Dynamics' Class II front splitter. Not only is the spoiler user-friendly on street cars, but race teams like Turner Motorsport and Global Motorsports Group have successfully used this splitter on their BMW 328 race cars in Speedvision Super Touring and USTCC championship races.
Racing Dynamics is a well-known BMW tuner that offers products ranging from aerodynamics to fully handbuilt motors for practically all series of BMWs.
RD's construction of the Class II splitter features a base manufactured out of PUR-RIM and the actual splitter out of ABS plastic. It replaces the plastic front lip on the bumper cover as seen on non-luxury version M3s. This is nice, because rather than sit 1.5 in. lower like the O.E. BMW unit, the RD splitter doesn't hang any lower than the stock lip did. Furthermore, the RD Class II splitter proved to be fairly light, weighing only 9.75 lb (RD also sells a replica, non-adjustable DTM splitter, similar to the ones seen on M3 lightweights).
When I received the unit, I drove Project M3 to Jeff Toberg once more. He did a really trick job molding the wing to the front bumper cover, revealing no lines where the bumper ends and where the RD piece begins. Additionally, Jeff refitted the undertray of the splitter so as to let it stick out an extra 1.5 in. over the intended 2 in. This way Project M3 could sport an aggressive 3.5-in splitter setup-much closer to the 4-in. extending BMW GT unit without getting banged up on the streets.
Although public street speeds effectively limit the effects of Project M3's new aerodynamics, I do believe the car is much more planted when traveling at speeds over...well...let's just say you can feel the aerodynamic effect when you're going really damn fast. However, more realistic results will be realized only on a road course. Stay tuned.
Turbo Update: The fun is over...but only for now
The good news is evosport fixed the front swaybar problem I had earlier, which included not being able to mount it-really not a setup I recommend in a powerful rear-wheel-drive car! The car had a dramatic oversteering problem (although it wasn't too bad for street use) from the front, passenger-side swaybar link not clearing the turbo compressor piping. Since the Advance Design shock housings are not exactly like stock, we were off just by a few millimeters. But with verbal help from Karl Hugh of Active Autowerke, evosport technician Frank Lopez precisely measured out the additional clearance the front Eibach swaybar would need. He then cut each original swaybar link in half, welded a steel tube to lengthen it, and reattached the front swaybar. We had clearance, and I could now push the car much harder around turns.