Help on casting codes
Thread Starter
Drifting
Joined: May 2006
Posts: 1,544
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From: Youngstown Ohio
Help on casting codes
I have gone through a dozen casting code sites but have not found what I'm looking for.
The block is reliably reported to have been bought from GM as a 1970 LS6 4 bolt to be built as a racing engine. The block codes read 3963512 thats the easy one.
What I can't find is: 1) sideways on the bolt flange ( date code) CONV, and 2) above that turned 90% is stamped GM6.
Photo of driver side rear of the block.....thanks Guru's
The block is reliably reported to have been bought from GM as a 1970 LS6 4 bolt to be built as a racing engine. The block codes read 3963512 thats the easy one.
What I can't find is: 1) sideways on the bolt flange ( date code) CONV, and 2) above that turned 90% is stamped GM6.
Photo of driver side rear of the block.....thanks Guru's
Last edited by 73-84 IMSA Widebody; Dec 11, 2007 at 06:30 PM.
Burning Brakes
Joined: Feb 2007
Posts: 779
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From: San Bruno California
3963512 is a 454 with 390hp for 1970, 365 & 425 hp for 1971
Go to corvette-world.com It's been helpful to me. Tony
My bad, didn't read all the way. You looking for the GM6 meaning.
Go to corvette-world.com It's been helpful to me. Tony
My bad, didn't read all the way. You looking for the GM6 meaning.
Last edited by 69 Convertible; Dec 11, 2007 at 09:36 PM.
Thread Starter
Drifting
Joined: May 2006
Posts: 1,544
Likes: 0
From: Youngstown Ohio
The front right pad is blank which is expected, block # 3963512 is expected, its the date code "CONV" and the GM6 which I can't find......The block was not Corvette but it and the frame were provided to run IMSA.
After further review "CONV 1"
After further review "CONV 1"
Last edited by 73-84 IMSA Widebody; Dec 11, 2007 at 09:48 PM.
Thread Starter
Drifting
Joined: May 2006
Posts: 1,544
Likes: 0
From: Youngstown Ohio
I found on a site that the CONV was simply a foundry mark.
The date code was on the passenger side rear flange, "j24 0" or Oct. 24, 1970.
If the GM6 is the 6th mold then all questions are answered.
Next one....what is the 020 under the timing chain cover?
The date code was on the passenger side rear flange, "j24 0" or Oct. 24, 1970.
If the GM6 is the 6th mold then all questions are answered.
Next one....what is the 020 under the timing chain cover?
probably more shift/worker/mold etc. marking which most likely never were kept record wise.
