SBC Cam Button

[billscamaros]

So, what exactly does a cam button do? I assume that it positions the camshaft in the correct position and ensures that the cam does not move fore or aft. Is that right?

The SBC 350 in my Camaro doesn't have a cam button in place. Are there different size (thickness) buttons, depending on the timing cover used? Do you always use a cam button?

Thanks

Bill

[waynieZ]

Yes thats right . With roller cams it got to be there with flat tappet lifters not as critical. When the cam moves forward I'm pretty sure the timing will change a little. Some one correct me if I'm wrong.

[70rs]

As I understand it,.on a flat tappet cam and lifters the there is a very slight angle ground in the lobes that ” forces” the cam to stay back in the block. The forces from the lifters sort of push it rearward. On a roller cam the angle is not there, it would cause issues with how the rollers ” track” on the cam lobe. That is when a cam button comes in. They are spring loaded and keep pressure on the cam, ” pushing” it back in the block and keeping it in the correct position.

Or something like that........

[GregWeld]

Originally Posted by billscamaros

So, what exactly does a cam button do? I assume that it positions the camshaft in the correct position and ensures that the cam does not move fore or aft. Is that right?

The SBC 350 in my Camaro doesn't have a cam button in place. Are there different size (thickness) buttons, depending on the timing cover used? Do you always use a cam button?

Thanks

Bill

Cam buttons are only required for ROLLER CAMS.... a flat tappet cam has a slope built into the lobes which walks the cam to the REAR of the block as it turns -- a roller cam doesn't have that so it walks fore and aft. A cam button holds it "back" against the rear of the block. There are adjustable versions - usually included in the timing cover (cast versions) or there are nylon style buttons. You can also run into issues with certain water pumps and the timing chain cover using cam buttons and sometimes need to clearance the bolt heads on the rear of the pump.