Can a standard cam gear be drilled to accept comps degree bushings? I have a new timing set.It has provisions on the shaft sprocket to advance or retard the cam 4 degrees,but all I need is 2 degrees.

 

Yea, I think that's the idea - to drill it for the bushings.

 

In theory, yes.

In practice however, how accurately can you locate those holes, with the tools at your disposal? Close enough that the whole deal is calibrated to within a couple of tenths of a degree of rotation? or even 1 degree?

4° is a very minor tweeek. 2° is near imperceptible; probably wouldn't move the power band by more than 100 RPM or so. Not to mention, timing chains don't all "stretch" the same amount: I'd be willing to bet that there's more than 2° of variance in that. In other words, you're into the "measure with micrometer, mark with chalk, cut with axe" kind of mode, because the natural behavior of the engine exceeds the effect of the change you're proposing to make. Especially if this is a street car (which I'm assuming it is, if you have a generic non-race timing set...).

Why do you think it needs moved 2°?

 

I have a ex268 cam with an Erson gear drive retared 2 degrees to keep DCR
at 8.17.Tired of the noise.Got a new comp timing set.Was going to use it,but
If I retard the cam 4 degrees would there be a problem with valve clearence?
RPM heads milled .030.piston .022 in the hole,.015 gasket.Quence is .037,
compression is 10.33
Thanks

 

No, should be OK.

Probably be better to just install it straight up though, and be done with it. Lots of people run that cam with more compression than that. What you have is a fairly common combo actually.

 

Thanks for the info.I will try it straight up and hope tunning wil keep detonation down.