1969 427 block and heads

[Thomas Chilton]

[Joe L.]

Re: 1969 427 block and heads

Thomas----

With a "CE" prefix block, the engine is not original to the car. That's pretty definite. Beyond that, a GM casting #3963512 block could be correct for a 1969 Corvette if the car was a later-build 1969. In this case, the casting date of the block is consistent with the car's build date. At least, it's consistent as far as NCRS/NCCB judging requirements are concerned. However, the fact that it's a "CE" block indicates that it is a replacement engine. Given the date of the block, I'd say that it was a very early replacement using an engine or short block that had been in inventory for awhile. The date indicted by the CE stamping is really irrelevent to any issue. However, given the casting date, the engine almost certainly was machined and assembled within 3 months thereafter.

It is possible to have an engine with different cylinder head casting numbers. It's not common, but it has been noted on known-original engines. The dates on these heads seem too far apart, though, to have been originally installed on this engine or originally installed on the engine originally installed in your car. The February-dated head would not be considered correct for a car with the build date of yours.

Most '290' heads are machined for tapered seat plugs. However, an early one such as yours may be machined for gasketted-type plugs. Essentially, the plug configuration is the only usual difference between the '063' and '290' heads. So, an early '290' machined for gasketted plugs is functionally identical to an '063'.

[Steven C.]

Re: 1969 427 block and heads

I'm sure you'll get a lot of responses, many of the gurus on this board are expert in '69 big blocks.

But, as a novice, the dates seem all wrong. The idea that the CE stamping was on your decked original block makes some sense, but a July block seems way too early (my late June build block was cast in March, and that's long because of the strike.

I hope you can sort it out.

Steve

[Mark #28455]

Most likely a warranty replacement

Your date codes on the CE engine all match up. "F" is June, not February, so the block is July, one head is July and the second is June - no problem with those dates. There was probably a switch in the heads to the 1970 casting numbers about this time in the production run at Tonawanda. Seems the same thing happened with the 840 vs 291 heads too from the date codes I've seen on e-bay. The 512 block was used from about Nov 1968 well into the 1971 model year or 1972 as both 427 and 454.

Most factory hydraulic lifter BB were assembled within a few weeks of being cast due to the high volume produced so although your dates may be NCRS acceptable, they are not likely what would have been originally present.

CE blocks were used for warranty exchanges - remember, original owners FREQUENTLY floored and blew up their original engines, many "numbers matching" cars are actually restamps!

Good luck,
Mark

[John H.]

Re: 1969 427 block and heads

Thomas -

The "CE" block is a 5/50 warranty replacement short block (block, crank, rods, pistons, rings, bearings); the "CE072076" says it's the 22,076th "CE" replacement engine built at Tonawanda during the 1970 model year.

[Steve Antonucci]

Re: 1969 427 block and heads

Joe,

I believe that some '290 heads were machined as service replacements for the
'063 heads and as such would have the earlier gasket type spark plug seats.

Steve

[Joe L.]

Re: 1969 427 block and heads

Steve----

Yes, I agree. This would be especially true for '290' castings manufactured as early as these were. After about January, 1970, I would expect that most '290' castings would have been the tapered seat plug variety except those used to manufacture SERVICE heads for pre-1970 applications.

[Thomas Chilton]

Re: Most likely a warranty replacement

What source do you have for F = June? All of the materials I have researched have A = Jan, F = Feb and so on.

[Mark #28455]

cast iron dating

GM cast iron uses the following date codes:

A = Jan
B = Feb
C = Mar
D = Apr
E = May
F = Jun
G = Jul
H = Aug
I = Sept
J = Oct
K = Nov
L = Dec

M was occasionally used to denote a pilot type casting

I have never seen or heard of F = Feb on a cast iron casting. Where did you find that?
Thanks,
Mark

[Thomas Chilton]

Re: cast iron dating

Opps, My bad, Thank You