I remember years ago that the Junior Stocker cars with little 265's and 283's in a heavy car ran 50 lb. flywheels to help launch 'em.

I talked to Kip Martin recently and asked him what he used in his 64 1/2 Mustang with a 289, he said 35 lbs. with a 4-speed. He sits the car on the back bumper at launch every time. It's exciting to watch.