These non-SFI rated Small Block Fits Chevy flexplates are suggested whenever installing a new engine or transmission. This 153-tooth flexplate fits 1986-97 externally balanced S/B Fits Chevys (such as 4.3/305/350) with a 1-piece rear main seal. Single bolt pattern. 12-13/16" O.D. 3 on 10-3/4" bolt pattern for the torque converter. External Balance, 1986-1997 Fits V8. Make sure you choose the correct flywheel for your application by reading our tech article. Small Block Fits Chevy - How to Choose a Flexplate.