Light weight flywheels increase performance.

[d_m_kolb]

A lighter flywheel does help you accelerate faster, and gain or loose RPM faster.SCC did some quick math in regards to rotational inertial and weight.Using the standard honda civic gearing, loosing 6 lbs off the flywheel showed these mathmatical gains.In 1st gear, it was like shaving 266lbs off the carIn 2nd gear, it was like shaving 122lbs off the carIn 3rd gear, it was like shaving 65 lbs off the carin 4th, 40 lbsand in 5th, 29 lbs.In order for your engine to transfer "pistion" power into "roational" power, it has to accelerate the crank, flywheel, clutch assembly, the gears, the driveshafts, the brake rotors and the wheels/tire combo. That's A LOT of weight to try to get rotating. The more weight you can shave off parts, the easier it is to get them to rotate (move).BTW...in a recent comparison of flywheels.RPW's high Carbon steel Flywheel was 11.5 lbsFidanza's aluminum flywheel was 7.5 lbs.The stockers weight is (depending on your car) 14 to 24 lbs.Unorthodoxracing has a Aluminum Flywheel (8 lbs.)Plus they have some lightweight pullies that slow down the accessories which also increases HP! http://unorthodoxracing.com/pontiac_vibe.html