1967-1979 Buick 403-455 ,166-Tooth, External BalancedHays heavy duty flexplates for high performance and competition engines are constructed of a thicker than stock steel plate, enabling them to withstand the stress of high stall torque converters and today's high RPM engines. While factory stock plates tend to crack around the crankshaft hub when punished under high torque and RPM conditions, the thicker Hays Flexplate handles the force. These H. D. flexplates are supplied with a ring gear that is