The Edelbrock Accu-Drive Camshaft Gear Drive replaces a stock timing chain with a precision gear drive system. The gear drive can be easily installed by replacing the stock crank and camshaft sprockets with Accu-Drive gears and slipping in the idler assembly. The Accu-Drive gear drive system transmits power from the crankshaft gear to a full floating main idler which drives the camshaft gear. A unique feature of the Edelbrock Accu-Drive system is the ability of the main idler gear to float to an optimum position between the crankshaft and camshaft gears, assuring equal load sharing between the crankshaft and the camshaft gears. They provide up to eight degrees of cam-timing adjustment in two-degree increments and have offset bushings for easy cam indexing, as well as SAE 8620 steel gears that will operate at higher RPMs.