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Old May 11, 2019 | 05:51 PM
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Default Replacement block?

I have a 78 L-82, with a non original block, I think. When I got the car it had the original L-82 heads and intake manifold, but it looks like the short block has been replaced. The casting number is 14016379, which was only used in 77-79 years. Some one has painted the block and heads orange, but I noticed that the block still had some blue paint under the orange. I was curious what pistons were used in the engine, so I took out a spark plug put one of those small cameras in the chamber and found out that the pistons were flat top. Could this be a warranty replacement block? There are no numbers on the deck pad.
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Old May 11, 2019 | 09:31 PM
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Factory replacement blocks came stamped with a specific letter code. But, if that engine was rebuilt in later years the numbers could have been removed during the machining process. Very common .
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Old May 12, 2019 | 08:57 AM
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Unless it has a stamp on the pad that begins in "CExxxxx", it is not a warranty or GM over the counter replacement. There is no way to know what is in there without a tear down.
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Old May 12, 2019 | 09:24 AM
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No mention of numbers stamped on pad on right front of block. Are they not readable?
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Old May 12, 2019 | 10:00 AM
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I looked the best I could, and didn't see anything. I just thought it was odd with the flat top pistons and blue paint under the orange.
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Old May 12, 2019 | 02:37 PM
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The 78 OE engine was blue. The orange was bubbamarket anyway. That could well be orig engine. If pad is blank, block was decked. All engines say something when they leave the plant. Even boat engines. Try to find date code on block and heads. Compare to trim tag build date.
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Old May 12, 2019 | 02:53 PM
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im pretty sure that 78 L-82 had dished pistons. A replacement engine probably wouldn’t have used the original smog heads. Seems likely the original engine was rebuilt and decked, removing the pad numbers.
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Old May 12, 2019 | 03:52 PM
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L-82 pistons are flat tops. The block casting is too late to be original. Its just a replacement engine with unknown internals.
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Old May 12, 2019 | 06:34 PM
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Originally Posted by stingr69
L-82 pistons are flat tops. The block casting is too late to be original. Its just a replacement engine with unknown internals.
Even in the late 70s.? Thought all smog era L-82s had dished pistons.
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Old May 12, 2019 | 07:50 PM
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Originally Posted by CA-Legal-Vette
Even in the late 70s.? Thought all smog era L-82s had dished pistons.
No L-82 were forged flat top.

L-48 did have cast dished pistons. That is why the compression is lower for the L-48.


1980 L-82 stock block
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Old May 13, 2019 | 12:06 AM
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I will try to find a date code for the heads for sure.The casting number for the heads is 462624, but has screw in studs and guide plates. Where would the date code be on the block?
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Old May 13, 2019 | 11:20 AM
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Originally Posted by ptaleo
I will try to find a date code for the heads for sure.The casting number for the heads is 462624, but has screw in studs and guide plates. Where would the date code be on the block?
On the back of the block between the distributor and drivers side head.

https://www.chevellestuff.net/qd/blo...ng_by_year.htm

Last edited by CA-Legal-Vette; May 13, 2019 at 11:22 AM.
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Old May 13, 2019 | 12:49 PM
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Mortec casting number page has broader year range
https://www.mortec.com/castnum.htm
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Old May 13, 2019 | 01:01 PM
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Originally Posted by jackson
Mortec casting number page has broader year range
https://www.mortec.com/castnum.htm
Maybe original block????
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Old May 13, 2019 | 11:28 PM
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I looked on the rear, passenger side of the block for a casting date and the only thing I found was 283 in large numbers, between what looks like the imprint of 2 screws. The manufacturing date on the car looks like K06.
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Old May 14, 2019 | 09:23 AM
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Originally Posted by CA-Legal-Vette
On the back of the block between the distributor and drivers side head.

https://www.chevellestuff.net/qd/blo...ng_by_year.htm
Originally Posted by ptaleo
I looked on the rear, passenger side of the block for a casting date and the only thing I found was 283 in large numbers, between what looks like the imprint of 2 screws. The manufacturing date on the car looks like K06.
Block Casting DATE:
Look on DRIVER side of Block ... View from ABOVE ... REAR of Block ... Adjacent to Bellhousing ... Between Distributor Mount and DRIVER side Head
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Old May 14, 2019 | 09:30 AM
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Originally Posted by ptaleo
I will try to find a date code for the heads for sure.The casting number for the heads is 462624, but has screw in studs and guide plates. Where would the date code be on the block?
Heads have a Casting DATE also.
With valve cover off ... Look around, in between, beside valve springs.
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