Question About Casting Numbers
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Le Mans Master
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Question About Casting Numbers
I understand that GM used the 327 in a number of vehicles over a number of years. Casting numbers on my 66' 327/300 show up on the Chevelle...Camaro....even some El Camino's. My question is.... What is the difference in the Corvette 327 block.... and the block's used in those vehicles? Casting number is the same. Is the motor...essentially the same? Thanks.
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Corvette block cast date has one digit for the year. Passenger blocks had 2 digits.. Now that's the way it is in my 63 but not sure about other years. But it is an interesting question and I would like to know too.
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By the same token, ALL small blocks with two digits for the year came from Tonawanda and no Tonawanda small blocks were used in Corvettes.
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Corvette small blocks have a single digit for the year because ALL Corvette small blocks came from Flint. All Flint small blocks have a single digit for the year, regardless of whether they were bound for Corvettes or not.
By the same token, ALL small blocks with two digits for the year came from Tonawanda and no Tonawanda small blocks were used in Corvettes.
By the same token, ALL small blocks with two digits for the year came from Tonawanda and no Tonawanda small blocks were used in Corvettes.
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As Jim says..........although there are a few (very few) exceptions. NCRS 1965 Judging Manual has this info. There was a brief period when swaps were done between Flint and Tonawanda engine plants for contingency planning. The block casting # is 3858180. It is a small block casting.
However ALL machining and assembly for Corvette small block engines was done at Flint............so they carry the "F" or the "V" (67) engine assembly prefix.
Tonawanda cast and machined all the big block engines during the C2 period.
Larry
However ALL machining and assembly for Corvette small block engines was done at Flint............so they carry the "F" or the "V" (67) engine assembly prefix.
Tonawanda cast and machined all the big block engines during the C2 period.
Larry
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Le Mans Master
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From: Northern CA
The motor carries the "F" designation on the stamp pad... but indicates it's from a '66 Chevelle 327/300 hp. There are no VIN stamps on the pad leading me to believe it's not the original motor. The casting numbers from the rear near the bell housing match the casting numbers on the base model Corvette motor 327/300. Question is: Is this essentially the same block that came with the Corvette base model 300/327? Internals the same? Thanks.
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The motor carries the "F" designation on the stamp pad... but indicates it's from a '66 Chevelle 327/300 hp. There are no VIN stamps on the pad leading me to believe it's not the original motor. The casting numbers from the rear near the bell housing match the casting numbers on the base model Corvette motor 327/300. Question is: Is this essentially the same block that came with the Corvette base model 300/327? Internals the same? Thanks.
As already mentioned, Corvettes ONLY received small blocks from Flint. BUUUUUUUUUUUUT, Flint built engines also went into mega thousands of other Chevrolet vehicles-----------------------and so did Tonawanda built small blocks-----------------------BUT NOT CORVETTES.
If a Corvette does not have its born with engine, then it is NOT a numbers matching engine -----------------------ESPECIALLY if it has a Tonawanda built engine. BUUUUUUUUT, if a Flint engine, with the correct casting date was located, and when it was machined at the machine shop, and the machine shop "accidentally" surfaced the decks and removed the STAMPED numbers from the stamp pad, then it sorta kinda could pass as a correct engine. That's all I'm going to say about that------------------you can read between the lines.
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The 66 Chevelle never had a advertised 327 with 300 hp. It only had the 327/275 engine which by rule of GM no vin stamp on the engine pad. Has only engines with a advertised HP of 300 or above in passenger cars got a vin stamp. But basically it was the same engine as the Corvette 300 minus the carb and exhaust manifolds. But the block was identical. There is no such thing as a corvette only block
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Is this essentially the same block that came with the Corvette base model 300/327? Internals the same? Thanks.
Ken asked if the internals were the same. As you stated, carb and exhaust manifolds were different. Block was the same. I would venture to say the pistons, crank, rods, cam, and valves were also the same.
Agree??
Larry
Ken asked if the internals were the same. As you stated, carb and exhaust manifolds were different. Block was the same. I would venture to say the pistons, crank, rods, cam, and valves were also the same.
Agree??
Larry
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sure do. all but the oil pan, carb, dist, exhaust manifold, air cleaner, and stickers its the same. Flint was casting and building 300 engines a HOUR. the more shared parts the better.
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Edit: misread your post. Sorry! You got it.
Last edited by DinoBob; Apr 15, 2021 at 11:29 PM.
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Flint blocks were CAST at the Saginaw foundry (about 30mi north), then shipped to Flint for machining and assembly.