So, now that we have tires and wheels installed, it’s time to find out how much quicker around our test track this combination is versus the O.E. tires and wheels. To simulate the total lap time of a typical national level autocross event, we combined 2 flying laps of our standard test course.
First setting a baseline reference with the factory 205/45R17 Bridgestone Potenza RE050A tire/O.E. wheel package, we then bolted on the 255/40R17 Dunlop Direzza Sport Z1 Star Spec tires on 17x9.0 TRMotorsports C3 wheels and ran a few comparison laps. With nothing else done to the car, and no real tuning done to optimize tire performance, we went well over 2 seconds a lap faster, on a 55-second course. Steady state lateral g-forces were improved, too.
We’re looking forward to installing the coil-over suspension, so we can better control the performance of the Dunlop tires.