Help decoding my motor
#1
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Car: 1987 Iroc Z28
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Help decoding my motor
I bought this motor and am having trouble decoding the partial Vin , can someone please help?
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Re: Help decoding my motor
Old enough that whatever that motor is now, is about 99.99999% CERTAIN to bear ABSOLUTELY NO RESEMBLANCE WHATSOEVER to whatever those numbers represent, with the possible exception of its CID. Which the numbers that ACTUALLY MATTER, the casting numbers, will tell.
Once a motor has been rebuilt, or had a cam swap, or a head swap, or a thousand other things, those numbers are WORTHLESS.
CMJ decodes to either a 80 LG4 (305) or a 74 350 which will be one of those 160 HP wonders from the deepest darkest smogger days. Let's hope that the motor YOU ACTUALLY HAVE is as different as possible from either of those 2 origins for the block casting.
Not to be mean or anything, but why in the world would you BUY a motor without knowing WHAT IT ACTUALLY IS, and then post "what did I just buy"????
Once a motor has been rebuilt, or had a cam swap, or a head swap, or a thousand other things, those numbers are WORTHLESS.
CMJ decodes to either a 80 LG4 (305) or a 74 350 which will be one of those 160 HP wonders from the deepest darkest smogger days. Let's hope that the motor YOU ACTUALLY HAVE is as different as possible from either of those 2 origins for the block casting.
Not to be mean or anything, but why in the world would you BUY a motor without knowing WHAT IT ACTUALLY IS, and then post "what did I just buy"????
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Re: Help decoding my motor
Well it was a 50 dollar motor for starters , but the casting number is 3970014. Can you decide the partial Vin?
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Re: Help decoding my motor
Sure can't.
It's a 4" bore block. Therefore sounds like it's the 74 350. Probably a full-size car. (Impala) Looks alot like my 74 Caprice's VIN FWIW. Except, my car has a 454, not a 350.
What info do you suppose the VIN would give you? Like, would it matter for example what color the car the BLOCK (not the MOTOR necessarily) came in was? Maybe there's some other better more sensible way to find out something "actionable" (able to meaningfully influence future decision making) or otherwise "useful"?
It's a 4" bore block. Therefore sounds like it's the 74 350. Probably a full-size car. (Impala) Looks alot like my 74 Caprice's VIN FWIW. Except, my car has a 454, not a 350.
What info do you suppose the VIN would give you? Like, would it matter for example what color the car the BLOCK (not the MOTOR necessarily) came in was? Maybe there's some other better more sensible way to find out something "actionable" (able to meaningfully influence future decision making) or otherwise "useful"?
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Re: Help decoding my motor
Was just trying to figure out its history , it's going to get a full rebuild but yeah that's all the info I was getting as well .
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Re: Help decoding my motor
trying to figure out its history
Beyond that:
It's a 70s smogger POS. Or at least, started out life that way.
It has LONG SINCE FORGOT its "history". Cast metal has an amazingly short memory for what sheet metal it came wrapped in when new, or even what it was LAST wrapped in. It's a 1974 block, and it's 2017 now. It's a forking ANTIQUE. There's NO TELLING where all that thing has been. Coulda eeeeeezily been in a dozen vehicles by now. That's probably something you don't want to know... kinda like asking her on the first date how many other men she's ... ummmm yeah. Doesn't matter. Won't help you, going forward. It IS what it IS, no more and no less.
Let's hope that as much as possible of what made it what it originally was, is gone; and that it's still useable for something. For that, you need to MEASURE stuff, as opposed to worrying about "VIN".
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I've never gotten proficient at decoding VIN stampings because, as already related, it won't have any bearing on what you end up doing. Once you deck the block (and from the looks of the rust on the deck surface, you'll be doing that), the VIN will be gone. All that will matter is whether the block is cracked, how well it was machined (if it's a '74 block, that doesn't bode well), and if your starter will bolt up to it.
Assuming it isn't cracked (which should be checked before you spend any more money on it), you'll want it thoroughly measured (as already suggested). If the lifter bores aren't aligned properly to the cam (all too common back then), don't spend another dime on it. If it is okay so far, it will likely need decking to clean and square the head gasket surfaces, likely need align honed to get the main bearings straight, and I assume the cylinders bored (hopefully they'll clean up at .030" over).
All that regardless what your end plans are.
What are your plans?
Assuming it isn't cracked (which should be checked before you spend any more money on it), you'll want it thoroughly measured (as already suggested). If the lifter bores aren't aligned properly to the cam (all too common back then), don't spend another dime on it. If it is okay so far, it will likely need decking to clean and square the head gasket surfaces, likely need align honed to get the main bearings straight, and I assume the cylinders bored (hopefully they'll clean up at .030" over).
All that regardless what your end plans are.
What are your plans?