1967 Corvette Small Block Cylinder Heads

[Peter L.]

1967 Corvette Small Block Cylinder Heads -



The 1967 Corvette TIM&JG, 5th Ed has the following "Reference" in the MECHANICAL SECTION, 3. Cylinder Heads on p. 103 that reads as follows:

Reference: The correct cylinder heads casting number is 3890462 for all cars except very late casting 3917291, with alpha-numeric date code which precedes the manufacture date of the car. Neither is visible as installed, nor are they judged.


Since the late casting 1967 small block 3917291 heads have a "boss" or place on the side that is NOT drilled & tapped; but is drilled & tapped for the temperature sender in 1968 and 1969; the question is is this feature considered in 1967 judging & if so when in 1967 did the 3917291 heads start showing up on the 1967 small block engines?

Thanks, Pete

[David L.]

Re: 1967 Corvette Small Block Cylinder Heads

Pete,

I would the assume that when the 3917291 cylinder heads were first cast then the the 3890462 cylinder head were no longer cast.
I have seen date codes as early as "E187" (May 18, 1967). I would think that cars made in June of 1967 could have the 3917291 cylinder heads.

Dave

[Gene M.]

Re: 1967 Corvette Small Block Cylinder Heads

When the 3917291 cylinder heads were produced for the end of the 67 model year production were the end casting threaded holes machined in?

Those 3917291 cylinder heads dated "E187" (May 18, 1967) if they have the large thread for the temperature sending unit could be for early 68 production.

[Peter L.]

Re: 1967 Corvette Small Block Cylinder Heads

Dave - Thanks. Pete

[David L.]

Re: 1967 Corvette Small Block Cylinder Heads

I assume that the cylinder heads and blocks were cast in the same plant. If so, here are a few "late" examples of 1967 Corvette 327 ENGINE casting dates along with stamped dates on the pad from Noland Adam's 63-67 restoration book:
V0525HH & E177
V0522HT & E167
V0629HT & F287 (VIN 194677S22893)
Total 67 Corvette production was 22,940.

Dave

[John H.]

Re: 1967 Corvette Small Block Cylinder Heads

My June 8th-built '67, #20401, 300hp engine built 6/1/67, has #291 heads that were cast on May 23.