80022 - 6.5" 350/400/403/425/455 Olds V8 Harmonic Damper

Oldsmobile Harmonic Damper 6.5" V8 350/400/403/425/455. This is an externally balanced damper with a bolt-in counterweight which can be removed for a neutral balanced rotating assembly. This damper will work on 330/350/400/403/425/455 cubic inch Old's engines. The damper features the stock Old's accessory pulley bolt pattern as well as a Big Block Chevy bolt pattern for those who may want to run a crank trigger system. Use of Chevy pulleys will require some machining to damper. Note: On 330 engines, TDC mark must be repositioned. This damper fits late 400 and 425 only. Early 400/425 engines have a different counterbalance than provided. A good balance shop can modify counterbalance to work correctly on early 400 or 425 engines.