PRW 1835001 SFI-Rated Internal Balance 168 Teeth Chromoly Steel Flexplate for Chevy 1957-85, 90 Early, V6 SFI 29.1 certified 0.035 inch thicker than stock flexplates Designed and built for racing Manufactured to exceed OEM specifications Features double-welded ring gears designed to withstand the RPM and stress of engine torque related to high stall converters