Professional Products 80022 Harmonic Damper

These are externally balanced dampers with bolt in counterweights which can be removed for a neutral balance engine

This damper has both the stock Olds pulley bolt pattern as well as big block Chevy

TDC mark must be repositioned for 330's and damper fits only the late 400 and 425 only

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 Olds engines. The damper features the stock Olds 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.
Brand: Professional Products, Model: 80022