Camshaft identification----Joe?

[George W.]

I pulled the high horse solid lifter camshaft fron an 3782870 327 block I am selling. I would like to identify it for future use. Numbers stamped on the rear end are: 611515A4; characters cast into the shaft are: CMC and CWC, D2, 30 ** K, and the last appears to be 6981 (only the six is clear). There is a yellow paint band also.

Do these numbers/charactors tell the grind, year of production, or intended use for this camshaft?

Thank you, george

[Duke W.]

Re: Camshaft identification----Joe?

My guess is aftermarket.

Chevrolet cams of the era have the seven digit finished camshaft number molded into the casting or sometimes just the last four and "6981" doesn't match any OE production Corvette cams.

Also, GM cams have the tooling set number molded in - like "GM5" or "GM12" and usually don't have stamped characters.

All Chevrolet cams were ground on specific blanks, so the finished part number cast into the blank is positive ID for both the blank and finished cam.

Aftermarket vendors grind many different lobes on the same blank, so they are usually stamped to ID the specific finished camshaft.

Duke

[George W.]

Re: Camshaft identification----Joe?

Duke,
The 6981 number is actually 1539. I was looking at it upside down the first time around. Where do you find the info on GM grinds? Thanks, G.

[Duke W.]

Re: Camshaft identification----Joe?

Still not a match for any production vintage Corvette cam. There are only three OE production mechanical lifter cams. The following are the finished cam/assembly part numbers. The first number is molded into the cam, the second is the service part number for the camshaft/pin "assembly".

Duntov 3736098/3736097
30-30 3849347/3849346
LT-1 3972182/3972178

The best information source is the engineering drawings.

What are you looking for?

Duke

[George W.]

Re: Camshaft identification----Joe?

Duke,
I am trying to identify the specs for this cam in case it would "fit" a future engine project. Thank you, G.

[Duke W.]

Re: Camshaft identification----Joe?

With the cam in the engine use a dial indicator to take a lift-crankangle diagram either at the lifter or the pushrod end of the rocker arm.

This is the only way to get any idea of the cam's characteristics unless you can positively ID it and find the manufacturers basic specs.

Duke