What is camshaft end play?

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What is camshaft end play?

Editing Date：2025-06-09

Definition and Description

End play is how far the camshaft moves in the engine block, from back to front. It is sometimes referred to as how far the cam will "walk."

End play only applies to Roller Camshafts. Flat tappet cams have tapered lobes that force the camshaft toward the back of the engine block. When installed correctly, flat tappet cams will not walk.

How is it measured?

Generally, the recommended amount of end play is between 0.003 in. and 0.010 in. Always follow the camshaft manufacturer's instructions when measuring and adjusting.

To measure and adjust end play:

1.	Install the Camshaft, timing gear, and any other related components.
2.	Torque all fasteners to the manufacturer's recommended specs.
3.	Set up a Dial Indicator on the end of the camshaft using a magnetic base.
4.	Push the camshaft as far back in the block as it will go.
5.	Set the dial indicator to read zero.
6.	Pull the camshaft as far forward in the block as it will go.
7.	Check the measurement on the dial indicator.
	a.	The reading is the camshaft end play.

How does it affect performance

Some end play is good. It allows the camshaft room to expand as it heats up. It also creates a little wiggle room to reduce wear. However, too much end play can cause some issues.

Cam Lobes
Too much end play can cause the cam lobes to wear much faster than normal. The lifter should ride on the center of the lobe. But as the camshaft moves, the lifter will ride on one side of the lobe. This can cause uneven wear.

Distributor Gear
When the camshaft moves in the block, it can cause the distributor gear to wear unevenly. It will also cause ignition timing issues and a loss of performance.

Damage to Parts
If the camshaft moves too far, the side of the lobe could come in contact with the lifter next to it. This can result in damage to the camshaft, lifter, and possibly the engine block.