TCI flexplates are035? t h i cker than stock and the starter ring is welded to both sides of the flywheel for additional strength. Constructed of high tensile strength material, these flexplates re s i s t elongation and cracking. All 168 tooth flywheels have dual GM Bolt patterns, are sized for stock 3/8? mounting bolts and can easily be drilled for high performance 7/16?. SFI approved.