How much clearance is there supposed to be between the two. I'm running a thich aluminum timing cover such as this one http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_754808_-1_11353 and it had a cast raised area on the inside I removed that which has got me close but i'm still probably .020" before the timing cover will sit flat against the block. I tried with a mr.gasket chrome cover I had laying around and it was way worse. I have a a roller button which is supposed to be .800" long I believe.

How much clearance is there supposed to be between the two. I'm running a thich aluminum timing cover such as this one http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_754808_-1_11353 (http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_754808_-1_11353) and it had a cast raised area on the inside I removed that which has got me close but i'm still probably .020" before the timing cover will sit flat against the block. I tried with a mr.gasket chrome cover I had laying around and it was way worse. I have a a roller button which is supposed to be .800" long I believe.
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Roller correct?
If not you do not need a button.
I like about .005" but it is not a critical deal
Anywhere from .002" to .010" is fine.

How much clearance is there supposed to be between the two. I'm running a thich aluminum timing cover such as this one http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_754808_-1_11353 and it had a cast raised area on the inside I removed that which has got me close but i'm still probably .020" before the timing cover will sit flat against the block. I tried with a mr.gasket chrome cover I had laying around and it was way worse. I have a a roller button which is supposed to be .800" long I believe.

You can buy adjustable cam buttons from Jegs/Summit/Comp Cams, etc... The adjustable cam buttons have different shims to achieve different clearances. You could also mill the existing cam button down, but make sure it is flat. The dimension/tolerance for cam shaft end play is .006"-.012".

HTH.

The button is a kind of a gold/zinc coated color, there looks to be a shim then the roller bearing then another shim. Can I take those shims out?

Below is a picture of the cam button like I was describing. These have been modified for different applications. In some cases the cam button has (the part that rides in the cam gear) has been milled down, in other cases the nose of the cam button has been milled. You can see an assortment of machined shims to go between the thrust washers. You can also shim the back of the cam button towards the gear/block. If it helps, you can run the thrust washer between the cam button base and nose without issue. I've done this in the past with no issues.

HTH.

What you refer to as thrust washers, I assume you mean the washers the between the button body and the bearing. Can these be removed?

OR is the thrust washer the bearing itself?

What you refer to as thrust washers, I assume you mean the washers the between the button body and the bearing. Can these be removed?

OR is the thrust washer the bearing itself?

The thrust washer is probably what you're refering to as a bearing (there are two pictured, left and right of the cam button base/nose) . The washers/shims (4 of them) are pictured below the cam button base/nose. The washers/shims can be removed. As I mentioned earlier I have ran just the thrust washer (bearing) and the base/nose of the button before without issue.

Great, thanks for the help.

Cam button to timing cover clearance is "ZERO" when cam is positioned such that the Rollers are Tracking in the Center of the Cam Lobes. You require a .003" to .008" Clearance between the Back Plate of the Cam Sprocket and Face of the Front Cam Bearing Boss on the Block.

I supply the roller buttons and alumiumn buttons to several companies. My roller button has a captive Torrington bearing that must have the matching wear washers on either side of it to work properly. I pulled the print on the aluminum button and it is .945" overall length.

I supply the roller buttons and alumiumn buttons to several companies. My roller button has a captive Torrington bearing that must have the matching wear washers on either side of it to work properly. I pulled the print on the aluminum button and it is .945" overall length.
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Read what Carl just posted.
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That was supposed to say Chris, not Carl :rolleyes:

This is what I would recommend too.

I would never run a thrust bearing against anything but the race it is designed to run against.
It may work but there is a reason they use the hardened & ground race (washer)

And while some specs may call for .006" to .012" I like to keep the clearance tighter
Crane calls for .005-.008, Comp says .005-.010, factory engines with thrust plates like the LS1, BB with a hyd rollers or all Fords as examples are anywhere from .001" to .012" so again, it is not a big deal.

Anything between .002" & .010" is fine with me with .005 or less preferred.
You can machine the button, shim the button, install a weld tab in the cover if necessary, whatever it takes to get the thrust correct.

Carl, who is Carl?.......Time to get some sleep Mike, J/King :)

Carl, who is Carl?.......Time to get some sleep Mike, J/King :)
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Well crap, how did I do that,,,
Thanks Brian,, Sorry Chris,,,, you know what I meant :beers:

You could also just use Comp Cams' nylon cam thrust button. You can easily shorten it yourself on a grinder, and it doesn't even load up the wheel, go figure. Just grind on the rounded end, not the precise flat end. Grind it to the length needed while keeping that rounded end rounded. It's not rocket science, you just need to get the end play you want. They are cheap, so I'd suggest getting a spare or two, just in case you accidentally grind one too short, don't ask me how I know. The nylon is of course, not high tech, but it will last nearly forever (no parts to wear out or fail, which occasionally happens with the needle type). It also is nearly frictionless, just try spinning the cam/button assembly against the cover in an otherwise empty block, and you will see that you can feel virtually no drag at all. So its all good. That's what I ended up having to do on my current 540 because the combination of all the parts ended up needing a button that was a little too short to run a needle type.