S.A. Gear 78410 Dual Idler Timing Gear Drive Kit Big Block Chevy

The S.A. Gear 78410 is a dual idler timing gear drive kit designed for big block Chevrolet engines from 1965 to 1997 with 396 to 454 cubic inch displacements. This precision-engineered gear drive system replaces the traditional timing chain with a robust gear-driven setup for improved accuracy and durability in high-performance applications.

Key Features:

• Dual idler gear drive configuration with noisy operation (mechanical gear whine)
• 8620 carburized steel cam and crank gears for exceptional strength and wear resistance
• Adjustable cam gear with inserts for precise cam timing adjustment
• Fixed crank gear with single keyway design
• Includes Torrington thrust bearing for proper camshaft support
• Comes with offset bushings, cam button, and mounting bolts
• Coated in rust preventative for long-term storage protection
• Meets or exceeds OEM performance standards

This gear drive kit eliminates timing chain stretch and ensures consistent valve and ignition timing throughout the engine's rpm range. The adjustable cam gear allows for fine-tuning of cam timing to optimize performance for specific applications. Note that this is the "noisy" version, which produces the characteristic mechanical gear whine associated with gear drives. A quiet version (78410Q) is also available separately.