The stock ring gear as used on most flywheels is 1/2" wide and weighs about 2.5lbs. Since reducing rotating weight is critical to performance and with the ring gear being on the outer edge of the flywheel, any reduction in this is amplified trememdously. Our "Thin" ring gear is only 3/8" wide and weighs only 1.5lbs. Nice performance advantage!
The thin ring gear is for old type inertia type starters and used on our steel flywheel C-AEG619 and C-AEG421. Originally fitted to automatic cars and old cast flywheels when lightened by various tuning shops in the 79s and 80s which is not recommended for competition. 107 teeth.0.343"wide