'72 454 Pistons
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Pro
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From: Woodstock GA
'72 454 Pistons
I know a '72 is pretty low compression, but I just pulled the heads off one and found domed pistons. Is that normal (to make up for the huge chambers in the heads?)? I don't see any markings indicating an over bore, and everything else in the engine looks stock.
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72's are normally flat tops. Someone has changed something. Can you post a pic?
JIM
JIM
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From: Woodstock GA
Possibly an LS-7 piston? Looks similar at least.
The heads are:
3964291 1969-72 454 2.19 1.88 Closed 108
Here is the reason I initially tore it down:
Any idea what kind of compression this thing is making? Headgaskets were stock type steel shim.
Team Owner
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From: Crossville TN
Probably making 10.5 or more. That lifter is really worn down. I wonder what the mating cam lobe looks like??? Might be a 'soft' lifter; might need more zinc in the oil; might be a 'geometry' problem with the valve train parts selection. What do the other lifters look like?
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From: Woodstock GA
Probably making 10.5 or more. That lifter is really worn down. I wonder what the mating cam lobe looks like??? Might be a 'soft' lifter; might need more zinc in the oil; might be a 'geometry' problem with the valve train parts selection. What do the other lifters look like?
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From: Woodstock GA
One of my guys found a number on the pistons...3963550. LS6 pistons! How are these on pump gas? The car is going to get a fairly healthy hydraulic roller, and already has an MSD ignition.
Le Mans Master
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From: Oquirrh Mountains
St. Jude Donor '09
Those pistons were for a '70 only closed-chamber LS6 engine. They are listed at 11.25:1 compression. Usually they're a bit lower than this in reality. I don't see any bad detonation signs on your one piston so I would leave it alone unless the engine needs a rebuild.
Before you go any further, get the numbers off of the front of the engine pad. If what you have is a "genuine" LS6, it's quite valuable. What you have may be a crate engine, one a previous owner assembled using LS6 parts using the car's original block. OR it may be a NOM engine someone put together from parts. It's worth knowing before deciding what to do with it.
Before you go any further, get the numbers off of the front of the engine pad. If what you have is a "genuine" LS6, it's quite valuable. What you have may be a crate engine, one a previous owner assembled using LS6 parts using the car's original block. OR it may be a NOM engine someone put together from parts. It's worth knowing before deciding what to do with it.
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From: Woodstock GA
Looks like its an LS6...on the pad is T0113CRR, which I show as Tonawanda, Jan 13, LS6...so this engine was replaced at some point. I don't see a partial VIN on the pad, so maybe this is a replacement LS6 (though it appears to have been in the car a LONG time)?
The car's VIN is 1Z37W2S505234, so at least it is a real big block car (LS5).
The car's VIN is 1Z37W2S505234, so at least it is a real big block car (LS5).
Le Mans Master
Joined: Dec 2006
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From: Oquirrh Mountains
St. Jude Donor '09
Interesting. CRR indicates it was in a '70 chevelle, 450 hp with a th400 trans. so it does jive. There's no number below the CRR suffix? The VIN is usually smaller and can be a bit harder to see since they're usually covered in gunk.
If the casting number and dates on the back of the block agree, this is something a Chevelle guy would be interested in. Make sure the dates on the heads agree. As an example, a friend had an L78 396 from a 68 Camaro in his 66 corvette. I pulled it for him and it sold for $5500 in 2006. It completely paid for his 496 build. This would be worth more.
If the casting number and dates on the back of the block agree, this is something a Chevelle guy would be interested in. Make sure the dates on the heads agree. As an example, a friend had an L78 396 from a 68 Camaro in his 66 corvette. I pulled it for him and it sold for $5500 in 2006. It completely paid for his 496 build. This would be worth more.
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Joined: Nov 2007
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From: Woodstock GA
Interesting. CRR indicates it was in a '70 chevelle, 450 hp with a th400 trans. so it does jive. There's no number below the CRR suffix? The VIN is usually smaller and can be a bit harder to see since they're usually covered in gunk.
If the casting number and dates on the back of the block agree, this is something a Chevelle guy would be interested in. Make sure the dates on the heads agree. As an example, a friend had an L78 396 from a 68 Camaro in his 66 corvette. I pulled it for him and it sold for $5500 in 2006. It completely paid for his 496 build. This would be worth more.
If the casting number and dates on the back of the block agree, this is something a Chevelle guy would be interested in. Make sure the dates on the heads agree. As an example, a friend had an L78 396 from a 68 Camaro in his 66 corvette. I pulled it for him and it sold for $5500 in 2006. It completely paid for his 496 build. This would be worth more.
