1966 Engine Stamping
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1966 Engine Stamping
I am looking at a 427 engine that is supposed to be from a 1966 corvette. The engine stamping is T1230IMR 6 D149309. Can anyone help me decode this? I am having issues with the IMR??
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Chevrolet never used "IMR" as a suffix code on big blocks or small blocks. Additionally, a "D" in the VIN derivative, indicates the Doraville, GA assembly plant, which never assembled Corvettes.
A picture of the stamp pad, might help in decoding it.
A picture of the stamp pad, might help in decoding it.
Last edited by gbvette62; Dec 22, 2015 at 10:53 PM.
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From: WV
Here is a photo of the stamp pad. Thanks.
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The engine date and suffix, "look" like a GM stamping, but the 6D149309 are nothing like something GM would stamp. I'd guess that the second set of numbers, may be something stamped on the block, by an engine rebuilder in the past. Shops often would do this, so they could identify their work for warranty purposes.
What is the casting number and and date of the block? Is ita 66 block?
It sure looks like IMR, but could it possibly be something else, like TMR? There were an assortment of Chevrolet truck big blocks, that used a 3 digit suffix code starting with a "T", but these were all engines used in the 70's and 80's.
What is the casting number and and date of the block? Is ita 66 block?
It sure looks like IMR, but could it possibly be something else, like TMR? There were an assortment of Chevrolet truck big blocks, that used a 3 digit suffix code starting with a "T", but these were all engines used in the 70's and 80's.
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The casting number is 3855961. I don't have the date code in front of me and I won't until Saturday. I am out of town currently. I do know that the block says PASS on the back of the block and High Perf near the oil filter. When looking at the stamping in person I am about 99% sure it is IMR. I will post the date code when I get back home on Saturday. Thanks for your help this far.
The engine date and suffix, "look" like a GM stamping, but the 6D149309 are nothing like something GM would stamp. I'd guess that the second set of numbers, may be something stamped on the block, by an engine rebuilder in the past. Shops often would do this, so they could identify their work for warranty purposes.
What is the casting number and and date of the block? Is ita 66 block?
It sure looks like IMR, but could it possibly be something else, like TMR? There were an assortment of Chevrolet truck big blocks, that used a 3 digit suffix code starting with a "T", but these were all engines used in the 70's and 80's.
What is the casting number and and date of the block? Is ita 66 block?
It sure looks like IMR, but could it possibly be something else, like TMR? There were an assortment of Chevrolet truck big blocks, that used a 3 digit suffix code starting with a "T", but these were all engines used in the 70's and 80's.
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The 3855961 block is a 2 bolt 66-67 396 casting. It was generally used in Chevelles and Impalas, in either 325 or 360 horsepower versions. A 66 396/325 with a Powerglide was suffix code IGR, but I still can't find any listing for an IMR code?
I believe you'll find the casting date on the right hand side of that block, in front of the starter, and near the freeze plug.
I believe you'll find the casting date on the right hand side of that block, in front of the starter, and near the freeze plug.
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The date code is L 17 5. This should be December 17 1965. This would go along with the engine stamp of 1230. The block casting number was also for the 1966 427/390 used in the Corvette. The suffix for the 1966 Corvette 427/390 is IM. I am wondering if this engine has been rebuilt and the machinist added the R to symbolize rebuild or something. Any additional help is greatly appreciated.
The 3855961 block is a 2 bolt 66-67 396 casting. It was generally used in Chevelles and Impalas, in either 325 or 360 horsepower versions. A 66 396/325 with a Powerglide was suffix code IGR, but I still can't find any listing for an IMR code?
I believe you'll find the casting date on the right hand side of that block, in front of the starter, and near the freeze plug.
I believe you'll find the casting date on the right hand side of that block, in front of the starter, and near the freeze plug.
