The COBB Tuning 3-Series Sport Spring Kit is the best first step to a better handling and better looking car. The 1.4"/1" (Sedan/Coupe) drop front and the 1"/0.8" (Sedan/Coupe) rear lowers the car's center of gravity to improve cornering speed and response while also minimizing wheel gap for a sportier look. This aggressive stance reduces squat and wheel hop under hard acceleration. Spring rates of 148 lbs/in front and 456 lbs/in rear provide the sport feel without being unnecessarily harsh or bouncy. Road course tested and real world approved, the COBB Tuning Sport Spring Kit is the best direct replacement spring available for your 2007-2011 BMW 3-Series (Not applicable for xi or xDrive models).