I'm getting close to switching to a roller cam in the big block!

Kern Dog said:

Since I've never installed a roller cam in an engine that wasn't built with one, I still wonder about how all this will work.
The concept of the back side of the camshaft sprocket riding against the block seems weird even with a Torrington bearing. I haven't looked into how the cam button is modified for the required fore/aft limits of the camshaft. The limit that I read was .010 of an inch fore/aft. That confuses me, since the lobes in a roller cam are not tapered, the roller wheels on the lifters seem like they'd be fine with the wheel hanging off the edges a little. I'm just curious as to why they are supposed to restrict the fore/aft movement so much.
Back to the clearancing of the cam button....
I may buy a reinforced timing cover or weld a plate over mine. That makes sense.
Regarding the cam thrust button....
Let me guess....You must first measure the depth of the timing cover and gasket, then measure how far out the cam button sits out from the face of the block.....then somehow mill down the cam button to get to a number that is less than the depth of the timing cover by no more than .010.
I'm supposed to use a straightedge and plane across a tiny cam button to the face of the block? How is that done with accuracy?

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Kern Dog said:

This sure seems time consuming.

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BLK 68 R/T said:

Two things I can think of for the fore/aft movement limits of travel.
1. Any fore/aft movements will induce sliding instead of rolling of the lifter wheel.
2. Stress on the oil pump/dizzy drive gear.

When I did my motor I used one of the roller style cam buttons.
https://www.jegs.com/i/COMP-Cams/24...MIg-etpvjrjQMVUgKtBh2L4BwYEAQYASABEgId7_D_BwE

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Kern Dog said:

Thank you.
What did you do to get to the desired thrust clearance number? Did you have to mill away some material ?

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PRHeads said:

When using a stock timing cover and the Comp 204 rollerized button……..this is how I do it:

The button is too long to fit under the stock cover, so I take two sockets(big one on the outside, about 3/8” bigger than the button on the inside), and hammer a “dimple” into the cover.
Adjust as necessary for desired thrust clearance.

Some aftermarket covers will clear the 204 button.

View attachment 1882689

View attachment 1882690

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I take it the dimple in the cover means it won’t need any additional reinforcement?

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