Engine Research
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Intermediate
Joined: Jul 2025
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Engine Research
I have an L88 427 that I'm trying to get some research on its value. The block is stamped with 3963512 and the heads are stamped with 3873858. I believe this is a 435/427. I picked it up from a friend that purchased it as a crate motor. I currently have it in a 1979 Trans Am that someone is wanting to buy just as a roller. I may part with the big block but want to see if anyone is looking for these specific stampings.
Any help would be greatly appreciated.
Any help would be greatly appreciated.
Race Director
Joined: Oct 2000
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From: Shamong, NJ
The "512" casting block was used from 69-71 for every variation of 427 and 454, and in both 2 and 4 bolt main bearing configurations. The "838" casting heads are 66-67 396 and 427 closed chamber heads. It's not likely the block and heads were ever sold as a complete crate motor assembly.
On the right front of the block there should be a machined pad. If the engine was ever sold as a complete engine, and not just a bare block, there should be a series of letters and numbers stamped there to identify how the engine originally started life. The format will be a "T" for Tonawanda, four numbers for the month and day of assembly and a two letter code to identify the engine size and horsepower A block stamped T0213LR would decode as Tonawanda NY assembly plant (T), February (02) 13th day (13) 427/435 with a 4 speed (LR). Of course, what it started life as is no guarantee of what the engine is internally now, especially with a mismatched block and heads.
On the right front of the block there should be a machined pad. If the engine was ever sold as a complete engine, and not just a bare block, there should be a series of letters and numbers stamped there to identify how the engine originally started life. The format will be a "T" for Tonawanda, four numbers for the month and day of assembly and a two letter code to identify the engine size and horsepower A block stamped T0213LR would decode as Tonawanda NY assembly plant (T), February (02) 13th day (13) 427/435 with a 4 speed (LR). Of course, what it started life as is no guarantee of what the engine is internally now, especially with a mismatched block and heads.
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Melting Slicks
Joined: Nov 2006
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From: Apple Valley, MN
As mentioned, the 512 block has both 2-bolt and 4-bolt main configurations, with the 4 bolt used in all high horsepower applications. True L-88s also have a “7115” crank (which was nitrided) vs the “6223” found elsewhere. Rods have 7/16” bolts vs the standard 3/8”. Same with pushrods.
All L-88s came with the K-66 transistorized ignition system, and an aluminum intake.
As mentioned, all came with aluminum heads. Up until around June of 69 they are closed chamber and the post June engines had the 2nd design 074 open chambers.
All in all, you would need to provide some additional detail before an accurate value could be applied to what you have.
All L-88s came with the K-66 transistorized ignition system, and an aluminum intake.
As mentioned, all came with aluminum heads. Up until around June of 69 they are closed chamber and the post June engines had the 2nd design 074 open chambers.
All in all, you would need to provide some additional detail before an accurate value could be applied to what you have.
Last edited by 69L88; May 26, 2026 at 11:31 PM.
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Joined: Oct 2000
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From: Shamong, NJ
As MelWff said, the "CE" stamping indicates it was a warranty engine, or possibly an over the counter block. Unfortunately the CE code will not identify what the internals of the block are, all the stamping will tell you is the following:
CE - Chevrolet Engine
0 - 1970, the year the block/engine was assembled.
66628 - is a sequential assembly number. Big block CE numbers began with 60000 so the engine is the 6628th big block CE block assembled in 1970.
CE - Chevrolet Engine
0 - 1970, the year the block/engine was assembled.
66628 - is a sequential assembly number. Big block CE numbers began with 60000 so the engine is the 6628th big block CE block assembled in 1970.
