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Old Mar 1, 2015 | 12:04 AM
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Default "M" code on Engine Block

Does anyone know what the Letter "M" on the back of the engine means? It is located where the date would be.
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Old Mar 1, 2015 | 01:18 AM
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There arena few threads on here on the M block,maybe someone can post them here.
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Old Mar 1, 2015 | 07:09 AM
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Think all is covered here, starting with page 4:

http://www.corvetteactioncenter.com/...umentation.pdf

My friend wrote the article in the restorer and has collected some data from 69-72 cars. If you would like to share more info I can pass it on. Pm me.
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Old Mar 1, 2015 | 11:48 AM
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Originally Posted by karol
Think all is covered here, starting with page 4:

http://www.corvetteactioncenter.com/...umentation.pdf

My friend wrote the article in the restorer and has collected some data from 69-72 cars. If you would like to share more info I can pass it on. Pm me.
Thank you for posting this information. My forum search did not find anything before I posted this thread. Now I have something else to learn about. If these cars could only talk they would have quite a story to tell.

Jay
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Old Mar 1, 2015 | 08:40 PM
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Jay,
I have a base motor automatic 72 that has one "M" head. Engine is untouched with original intake gaskets, etc. if I recall, the number is M114, but I'm away from home for a couple of weeks and don't have documentation with me.
Mike

Last edited by 62corvette; Mar 2, 2015 at 01:09 PM.
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Old Mar 2, 2015 | 12:23 AM
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Originally Posted by 62corvette
Jay,
I have a base motor automatic 72 that has one "M" head. Engine is untouched with original intake gaskets, etc. if I recall, the number is M114, but I'm say from home for a couple of weeks and don't have documentation with me.
Mike

Hello Mike and thanks for your reply. I have to say that I had never heard of this "M" code until yesterday. I have read over the Forum article several times and I am trying to learn what it all means. I did not see anything about the heads but it might apply to them as well as the blocks. If I learn anything else I will post it.

Jay
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Old Mar 2, 2015 | 07:57 PM
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Does anybody have more that they can add to this topic. I have read everything so far that has been posted.Very good information there. I would like to know more since my block is the documented original to the car and it is a M 44 coded block.

Thanks
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Old Mar 3, 2015 | 09:35 AM
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Originally Posted by deejaydu
Does anybody have more that they can add to this topic. I have read everything so far that has been posted.Very good information there. I would like to know more since my block is the documented original to the car and it is a M 44 coded block.

Thanks
I believe that they were test castings that were samples for new tooling/change of metallurgy ETC. If all was well the blocks were sent to engine machine/ assembly.
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Old Mar 3, 2015 | 10:19 AM
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Originally Posted by kenba
I believe that they were test castings that were samples for new tooling/change of metallurgy ETC. If all was well the blocks were sent to engine machine/ assembly.
Thanks Ken for the information. That is my understanding as well. I do have documentation from Al Greenings company that references the "M" code and states that it is the original engine for the car. I just want to learn as much as I can about when they were used in production.

Jay
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Old Mar 3, 2015 | 10:21 AM
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Originally Posted by karol
Think all is covered here, starting with page 4:

http://www.corvetteactioncenter.com/...umentation.pdf

My friend wrote the article in the restorer and has collected some data from 69-72 cars. If you would like to share more info I can pass it on. Pm me.

Karol is your friend Gene Gamache. If it is could you please put me in touch with him.

Thanks
Jay
713-253-0475
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Old Mar 3, 2015 | 10:38 AM
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Yes, let me contact him first and send you a pm on the best way to correspond. Great guy
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Old Mar 3, 2015 | 11:07 AM
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Originally Posted by karol
Yes, let me contact him first and send you a pm on the best way to correspond. Great guy
Karol thank you so much. I am looking forward to speaking to him. His article is a great resource. I will reply back to your PM before I contact him.

Thanks for your help.

Jay Dumesnil
713-253-0475
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