Project LA Thumper Gets A Milodon Gear Drive For Precise Timing

When discussing the best way to link your engine’s cam and crankshaft, the conversation always seems to be a topic that leads to varying opinions. Ask any engine builder or enthusiast their opinion — whether it be about a chain, belt, or a set of gears — each one solicits a strong argument.

We’re at a point in assembling Project LA Thumper where we need to make the cam/crankshaft connection. While a timing chain would suffice, we decided to step it up a notch and chose to use a Milodon gear drive (P/N: 13600). We’ve heard the statements about issues with gear drives being noisy and initiating harmonics in an engine, so we asked Steve Morrison at Milodon about these concerns. “The talk of harmonics has been going on forever. While there might be some validity to it, no one has ever tested the theory. As far as noise, these are straight-cut gears, so there will be a small amount of noise, but it is minimal.”

Many enthusiasts have the opinion that a gear drive is best suited for a race engine. While that is true to an extent, a good gear drive is just as “at home” in any performance engine. When properly installed, we’re told a Milodon gear drive will last almost indefinitely. This is because there is nearly zero wear — again, if properly installed. Since cam timing accuracy and consistency are key to accessing every bit of the cam’s available power-delivering capabilities, a gear drive is a perfect option.

The idler gear and bracket are affixed to the block with the cam-plate bolts.

If you are looking for a gear drive to make more power, look elsewhere. A gear drive is not designed to increase power. What it is designed to do is create stable timing that does help with power production. As Steve stated, “anything flexible can stretch. “When a chain or belt stretches, that will affect your timing. With a gear drive, no stretch can occur.”

Gearing Up

The Milodon gear drive is made from billet steel. But, unlike other multi-gear sets, the Milodon drive uses a single idler gear that is rigidly mounted to a support bracket that affixes to the block. This rigid mounting does not allow any timing fluctuations like could possibly be found when using a flexible belt or chain that can, again, stretch over time.

Mounting the idler gear and its bracket is done via the cam-plate bolt…