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Jim - Welcome to the Corvette Forum. If you have the engine and can supply us with the stamped and raised block casting numbers, front pad and rear bellhousing flange, that would be helpful.
Also, on the heads, with the valve covers off, you should see some raised casting numbers, those would help too.
Mike T - Prescott AZ
Block casting 3959512
on the rear of the block by the passenger freezer plug
H23
532
512
Stamped on the block drivers side front
May be? CLOA3479
I’ve looked some of these up but the head casting I can’t figure out
Jim,
Using the chart that Keith posted above, you can look up the casting numbers on your head in the chart in the link below...they're, definitely, not original to your Corvette.
Jim,
Using the chart that Keith posted above, you can look up the casting numbers on your head in the chart in the link below...they're, definitely, not original to your Corvette.
Block casting 3959512
on the rear of the block by the passenger freezer plug
H23
532
512
Stamped on the block drivers side front
May be? CLOA3479
I’ve looked some of these up but the head casting I can’t figure out
I'm guessing the CL03479 is actually CE0 meaning it's like a CE service replacement block, as Nowhere Man said. "CE" blocks decode as:
"CE" - Chevrolet Engine. These were usually 5/50 warranty replacement blocks used from 1968 through the early 70's.
"0" - The year the block was assembled, in this case.
"A3479" is the CE block sequential serial number. Though thie stamping appears to be one digit short. **
** CE blocks used for V8's assembled at Flint MI were numbered 20000-49999, Tonawanda NY built CE V8's were number 50000-80000. When they reached 49999 at Flint or 80000 at Tonawanda they started over adding an "A" after the year as in the number above, then "B", "C" and so on. The pad stampings on a CE engine won't tell you anything about how the engine was built internally, all it tells you is the year it was assembled.
The 3959512 block was commonly used for 327 CE engines. To my knowledge the 9512 was not used as an assembly line production block, and was only used as a service replacement block. I'm pretty sure the 9512 is a large journal 327 block which would make it a pretty good block to build a performance engine from.
The markings on the heads look like the ones for 70's 267's and 305's to me? I hope I'm wrong because they're terrible heads. The only way to know for sure which heads they are is to pull a valve cover and take a look at the casting number.
I'm guessing the CL03479 is actually CE0 meaning it's like a CE service replacement block, as Nowhere Man said. "CE" blocks decode as:
"CE" - Chevrolet Engine. These were usually 5/50 warranty replacement blocks used from 1968 through the early 70's.
"0" - The year the block was assembled, in this case.
"A3479" is the CE block sequential serial number. Though thie stamping appears to be one digit short. **
** CE blocks used for V8's assembled at Flint MI were numbered 20000-49999, Tonawanda NY built CE V8's were number 50000-80000. When they reached 49999 at Flint or 80000 at Tonawanda they started over adding an "A" after the year as in the number above, then "B", "C" and so on. The pad stampings on a CE engine won't tell you anything about how the engine was built internally, all it tells you is the year it was assembled.
The 3959512 block was commonly used for 327 CE engines. To my knowledge the 9512 was not used as an assembly line production block, and was only used as a service replacement block. I'm pretty sure the 9512 is a large journal 327 block which would make it a pretty good block to build a performance engine from.
The markings on the heads look like the ones for 70's 267's and 305's to me? I hope I'm wrong because they're terrible heads. The only way to know for sure which heads they are is to pull a valve cover and take a look at the casting number.
Glenn,
All three of the head casting numbers associated with that cast marking are the one you mention...70s - 80s crap heads...267, 305, etc.
This stuff is like Raiders of the Lost Ark! Trying to decipher an ancient map! Thanks for the information. I am confined to my bed right now nursing a detached retina but will get to the shop next week.
So the engine in the car now is supposed to be a rebuilt 350, AI says the block should be a small journal 327 which would be expensive in the 80’s to turn into a 350 but it does have an 8” harmonic balancer? 327 should have a 6” balancer right?
