Professional Products 7.5 Inch Damper for LS-1/LS-1 Chevy Camaro/Firebird features the Powerforce plus SFI damper for the extremely popular LS1 engine. It represents one of the best values available in the high performance industry. This damper will also work on most LS1 based crate engines. Although not required on a stock engine, the dampers have a keyway and 60 degrees of timing marks. This damper is dimensionally identical to the stock O.E. damper.