Big Block cam ID

[John M.]

Im trying to ID two NOS bigblock cams I found in my shop, one has white and yellow inspection marks a casting date of F 25 #6930 GM 24, the other has a pink stripe on both ends and 8609 and GM 1, thanks in advance John

[Joe L.]

Re: Big Block cam ID

John-----

The "6930" is not a big block camshaft. It's the 67+ 327 and 350 "300 hp" cam. The GM part number for the camshaft assembly was GM #3896929.

I can find no reference to any camshaft with an "8609" ID number. However, there was once a small block camshaft with the ID number "3906" which may be what you're interpreting as "8609". That camshaft was the 55-61 283 cid hydraulic camshaft of GM PART #3704212. This camshaft may aslo have "2 circles" between one pair of lobes as a casting symbol.

[Duke W.]

Re: Big Block cam ID

The "6930" is more likely the '67-'80 Corvette base engine 3896930 finished camshaft (cam and pin assembly part number 3896929), commonly known as the "300 HP cam". This is a small block camshaft.

I don't have a reference to the 8609 on my list OE Corvette finished camshaft part numbers, but "8609" is the last four digits of the finished camshaft part number. The part number for the cam and pin assembly, which is the part number listed in parts catalog is likely very close close in sequence either side - probably no more than 50 and as little as 1.

Duke