59 head numbers

[Keith C.]

I have a February 59 fuelie, CS engine, solid lifter, w/ a 7014900R. The numbers on the head don't appear to be the original, but I'm not sure. There are four numbers:

1) 3774692 (which I believe is a 60 head, but not sure)
2) GM with the number 4 under it
3) J139 (which I'm guessing is Oct 13 of 59
4) Underneath the J139 is a 13, right under that is a 4 on a slightly raised circular cast.

Would this ever have been used on a 59 car?

Is this head correct for a fuelie CS solid lifter engine?

Any help understanding this would be greatly appreciated.

[Joe L.]

Re: 59 head numbers

I have a February 59 fuelie, CS engine, solid lifter, w/ a 7014900R. The numbers on the head don't appear to be the original, but I'm not sure. There are four numbers:

1) 3774692 (which I believe is a 60 head, but not sure)
2) GM with the number 4 under it
3) J139 (which I'm guessing is Oct 13 of 59
4) Underneath the J139 is a 13, right under that is a 4 on a slightly raised circular cast.

Would this ever have been used on a 59 car?

Is this head correct for a fuelie CS solid lifter engine?

Any help understanding this would be greatly appreciated.

Keith-----

1) The GM #3774692 cylinder head casting is a 1960 head. It was used for virtually all Corvette engines for 1960.

2) The number "4" under GM represents a pattern number used to make the sand mold for this particular head.

3) "J139" does decode to October 13, 1959. As such, it could not have been used on a 1959 Corvette since 1959's were out-of-production by that time.

If by "correct" you are asking would the 3774692 be NCRS-correct for a 1959 "CS" coded Corvette engine, the answer is no. However, it should be functionally correct in that it should work perfectly as a replacement for the original heads.

One more thing: most 1959 Corvettes used cylinder heads with "staggered" valve cover bolt pattern. Very late 1959's may have used heads with a "straight across" valve cover bolt pattern. The GM #3774692 heads have a "straight-across" valve cover bolt pattern. So, while head casting numbers and dates are impossible to discern (and, therefore, impossible to judge), the valve cover bolt pattern would be a dead-give-away (unless your car happened to be a VERY late 1959).

[Keith C.]

Re: 59 head numbers

Thank you for the clarification. I've read there are several head numbers for 1959 FI motors. Can you confirm which ones match a 02/59 FI CS engine?

[Tom B.]

Re: 59 head numbers

With the exception of possibly some very early 59s that used some carry over "770" '58 heads and the late '59s that used straight across valve cover bolts, all 1959 engines used casting number 3755550 staggered valve cover bolt heads. Heads dated from a couple days to a couple weeks before the engine assembly date would be perfect.