No block stamping
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Heel & Toe
Joined: Dec 2021
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No block stamping
The pad in front of the passenger head has no marking on it, nothing at all, smooth as glass. So, I think that would mean it is more likely to be a service replacement block vs a machined rebuilt one, right? Or when a block is decked, would it be glass smooth as well? That said, if it was decked, is there a way to "pull" the numbers into view? If a service replacement, how ethical is it to stamp it to match the car? I suspect not very but want to check.
*****update not concerned about re-stamping, just seeing if I can pull up any old stamp so thanks with any help there!
*****update not concerned about re-stamping, just seeing if I can pull up any old stamp so thanks with any help there!
Last edited by 70gtvert; Dec 24, 2021 at 11:24 AM. Reason: new info
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
Yes, if the block has been decked, it will have a smooth ID pad.
You can still find casting numbers and date codes to narrow down what you have.
Lars
You can still find casting numbers and date codes to narrow down what you have.
Lars
1967 Pedal Car Champion
Joined: Mar 2020
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From: US-PNW
A Chevrolet service replacement block should still be stamped - usually with a CE prefix. I'd say your block was decked.
I read, somewhere, that acid etching can bring up the stamp character shadows of the deformed cast iron. Never any experience with that but it could be an avenue for exploration.
I read, somewhere, that acid etching can bring up the stamp character shadows of the deformed cast iron. Never any experience with that but it could be an avenue for exploration.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
acid etching can help. Ive done it with firearms. The stamp hardens the metal underneath it and the acid eats the softer material around it. It helps if you can use a magnifiying glass to pick out any lines from the stamp before hand so you have a starting point. But be aware acids are acids and its best to do it in a controlled environment , not with an installed engine in your car. Too much to go wrong, even with a weak acid. IF its not too important wait to do something like that until youhave the motor out for rebuilding or something.
Safety Car
Joined: May 2001
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From: Fairfax Virginia
The stamping on the blocks is not a good indicator anymore as SO many people have re-stamped their new blocks. I would not believe it was a "Numbers Matching" unless an expert verified that with a Tank sheet in hand.
Re-stamping has become too common and the tools to do it are everywhere. IT is a dishonest thing to do but can make the car sale price jump which makes more folks do it.
My 1968 C3 has a CE stamped engine with the identifiers that it was a replacement engine for a 1967 L71 Corvette. The replacement block is dated August of 1967. Since the C3 started life in October as a 1968 L71 Convertible this engine works fine for me.
Re-stamping has become too common and the tools to do it are everywhere. IT is a dishonest thing to do but can make the car sale price jump which makes more folks do it.
My 1968 C3 has a CE stamped engine with the identifiers that it was a replacement engine for a 1967 L71 Corvette. The replacement block is dated August of 1967. Since the C3 started life in October as a 1968 L71 Convertible this engine works fine for me.
Is my vette stock?? HAHA
Joined: Oct 2015
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Likes: 9,350
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
My appraiser told me his appraisal would be $4000 more with the motor in the car...I have it under my bench. I ran 2 different motors with 4 different cams before I put the OG motor back in. Never had an issue with any of those motors. Blew the head gasket and filled my block with milkshake....such a disgusting mess with it. ITs back under the bench never to go back in. Im into big blocks now.
I go to a ton of car shows. Very few ask if the motor is original, the ones that ask get the truth, i have it, just not in it. No one really cares, its just a question.Then the talk shifts to whats in it and how fast it goes. They really want to know power numbers, top speed, etc...
Just leave it and worry about important stuff like how it runs and if its fun in th ecurves or not. You cant see it when your driving it. Truthfully, the only time I think about engine numbers, IF i think about engine numbers, is what displacement it is, not what is stamped on the pad
I go to a ton of car shows. Very few ask if the motor is original, the ones that ask get the truth, i have it, just not in it. No one really cares, its just a question.Then the talk shifts to whats in it and how fast it goes. They really want to know power numbers, top speed, etc...
Just leave it and worry about important stuff like how it runs and if its fun in th ecurves or not. You cant see it when your driving it. Truthfully, the only time I think about engine numbers, IF i think about engine numbers, is what displacement it is, not what is stamped on the pad
1967 Pedal Car Champion
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From: US-PNW
Ethics is in the eye of the doer and observer. I tend toward, no, it's not ethical to restamp a block -- even if it's the original block. The stampings imply that it is the same as it was originally and if you have to restamp it then it is not as it was when new. If my block was stampless, I'd explore the acid treatment but leave it at that - not restamp it. I believe that exhibits greater integrity than restamping.
