Chevy Small block V8 SMALL- BLOCK FLYWHEELS Part Year of Outside Crank Flange Clutch Starter Ring Technical Notes Number Engine Diameter Bolt Pattern Diameter Gear Teeth 14085720 1955–85 12.75" 3.58" 10.4" 153 For two-piece crank seal. Lightweight nodular iron; weighs approximately
14088646 1986–up 12.75" 3.00" 10" 153 For one-piece crank seal. Lightweight nodular iron; weighs approximately 14088650 1986–up 12.75" 3.00" 10.4" 153 Standard-weight flywheel for one-piece crank seal 3991469 1955–85 14" 3.58" 10.4"; 11" 168 For two-piece crank seal
10105832 1986–up 14" 3.00" 11"; 11.85" 168 For one-piece crank seal  SMALL- BLOCK FLEXPLATES Part Year of Outside Crank Flange Converter Starter Ring Technical Notes Number Engine Diameter Bolt Pattern Bolt Pattern Gear Teeth 471598 1970–85 14" 3.58" 10.75"; 11.50" 168 For internally balanced engine with two-piece crank seal
471578 1970–80 14" 3.58" 10.75"; 11.50" 168 For externally balanced 400-cu-in engine only. Use with balancer 471529 1969–85 12.75" 3.58" 9.75"; 10.75" 153 For internally balanced engine with two-piece crank seal 14088765 1986–up 12.75" 3.00" 10.75" 153 For one-piece crank seal
12554824 1986–up 14" 3.00" 11.50" 168 Heavy-duty flexplate with increased thickness for one-piece crank 14088761 1986–up 14" 3.00" 10.75"; 11.50" 168 For one-piece crank seal FLYWHEELS & FLEXPLATES Find the right part to match your engine from the easy -to-follow guides below. Select flywheels for manual transmission vehicles and flexplates for automatic transmission vehicles.
Note: IMPORTANT! All Chevy small-block and big-block engines with one-piece crankshaft seal require an externally balanced flywheel or flexplate. BOLTS 12337973 Flywheel Bolt (not shown) • Fits all Chevy small-block V-8, big-block V-8 and 90 V-6 engines • Sold individually; six required per engine 3727207 Flexplate Bolt (not shown) • Fits all Chevy small-block V-8, big-block V-8 and 90 V-6 engines • Sold individually; six required per engine |