well, the flywheel wouldn't make it harder to launch nor will it slow the car down between shifts. simply because when you shift, the car is basically in neutral...and once you engage the next gear, it revs back up to where it should be. i may loose 200 rpms from a stock flywheel...but that doesn't slow the car down at all. i'll be running the same rpm's as a car with a stock flywheel once i engage the next gear. it doesn't make the car rev like an indy car like everyone believes...it's just slightly quicker. and top end is the s***.