Trouble Centering Cam to Drive Sprocket

[polizei]

Hey Guys - I purchased a set of used Elgin Super C2 Cams from a shop in the northeast a few months ago, for use on my '87 Carrera. My engine builder is getting around to installing them now and noticed that the nose of the camshaft which interfaces with the drive sprocket has been milled or tapered such that there is no longer a machine fit between the drive sprocket and the camshaft, but rather a .020" gap - resulting in a sloppy fit. 2 questions:

1. Why would cams be milled here?
2. Can anyone recommend a solution?

These cams were installed on a 964 or 993 engine as they have the power steering drive. I'm a bit confused because 911s from 1970 through 1998 all use the same drive sprocket.

Thanks for your help!

[HawgRyder]

You can get shim stock in any thickness.
Perhaps a ring of such shim might be placed in the gap to centre the assembly, and then the fasteners can be tightened.
Or...hava a machinist make a couple of circlular shims (tight fit) to put on the gear (with a slight "L" shape to keep it in place).
Bob

[polizei]

Bob - Thanks for the quick reply. Is it normal to run shims for this much of a gap (.020")? I'd like to understand whether that's a safe, proven solution, or if I'd be better off getting another set of cams.

[HawgRyder]

New cams would be the better way...but if you in a $$ pinch...the shim idea will work.
The shims must be retained when the engine is running...you cannot use them for assembly and then remove them after tightening the bolts.
I have shimmed pieces before in several engines (old, special, no new parts available)...with good results.
As I said ...a machined shim with a thin "L" shaped lip would be best...so that the shim cannot escape.
Hope it helps.
Bob