SFI 18.1 Harmonic Damper for GM 98-02 LS1 F-Body & 04-06 LS1/LS2 GTO – w/ Crank Bolt. Features 6 Rib drive & 10% underdrive diameter pulley.

Underdrive dampers are for use on Naturally Aspirated engines making 700hp or less. For engines making over 700hp, please use a standard diameter damper for greater dampening capability.

This damper comes standard with 3/16″ Keyway for use with aftermarket crankshafts..

NOTE: Innovators West specific pin kit required when used with a stock non-keyed crankshaft.

• Diameter: 6.5″
• Weight: 7.8 lbs
• Exceeds SFI 18.1 standards and is marked on front with SFI Sticker, and on the rear with SFI number stamped into unit.