Learning about 1981 engine
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3rd Gear
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Learning about 1981 engine
Hello! I need help, I've acquired an original 1981 corvette engine, all I know is that it's a 350 cubic. I'm trying to sell it, but I would like more information on it before I do so. The vin number is V0515ZAK1AS431318
Also, how much is this engine worth? What price should it be sold at?
Also, how much is this engine worth? What price should it be sold at?
Last edited by Mamatofu; Oct 27, 2025 at 10:24 AM.
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From: At my Bar drinking and wrenching in Lafayette Colorado
That's not a 1981 Corvette VIN.
1981 Corvette VINs are in this format and range:
1G1AY8764BS400001 – 1G1AY8764BS431611 (Cars built in St. Louis)
1G1AY8764B5100001 – 1G1AY8764B5108995 (Cars built in Bowling Green)
ID numbers starting with "VO" are engine ID numbers - not VIN numbers. The engine ID stamp pad will have both engine ID numbers and a partial VIN number, which is usually the last 9 digits of the vehicle's VIN. If the "AS431318" is the partial VIN, it is not a 1981 Vette engine.
The "V" indicates the engine was built in Flint Michigan. "0515" indicates that it was built May 15th. "ZAK" is a 1980 350 Corvette 190 horse engine with 4-barrel carb and a turbo 350 tranny.
Lars
1981 Corvette VINs are in this format and range:
1G1AY8764BS400001 – 1G1AY8764BS431611 (Cars built in St. Louis)
1G1AY8764B5100001 – 1G1AY8764B5108995 (Cars built in Bowling Green)
ID numbers starting with "VO" are engine ID numbers - not VIN numbers. The engine ID stamp pad will have both engine ID numbers and a partial VIN number, which is usually the last 9 digits of the vehicle's VIN. If the "AS431318" is the partial VIN, it is not a 1981 Vette engine.
The "V" indicates the engine was built in Flint Michigan. "0515" indicates that it was built May 15th. "ZAK" is a 1980 350 Corvette 190 horse engine with 4-barrel carb and a turbo 350 tranny.
Lars
Last edited by lars; Oct 27, 2025 at 09:42 PM.
Drifting
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Of course it ain't a VIN; just the closest thing he's got to a VIN
Seems he acquired just a motor; not a car.
That ID is probably what he sees stamped into pad just forward of pass head.
Without seeing it in-person, seems like a legit stamp pad number; for almost mildest red-headed stepchild vette motor since Blue Flame.
Maybe someone here needs a 1980 vette's base L48L81 ? Now that he knows a little more about it, perhaps he lists in the C3 Parts For Sale ?
Otherwise, it's just another worn smog-slug 350
Seems he acquired just a motor; not a car.
That ID is probably what he sees stamped into pad just forward of pass head.
Without seeing it in-person, seems like a legit stamp pad number; for almost mildest red-headed stepchild vette motor since Blue Flame.
Maybe someone here needs a 1980 vette's base L48
Otherwise, it's just another worn smog-slug 350
Last edited by Rebelyell; Oct 27, 2025 at 04:12 PM.
Melting Slicks
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From: Fleming Island, FL
L81 is the same long block as the previous years L48 and LM1 engine with the exception of tubular exhaust manifolds, electronic spark timing and feedback carburetor, and cast valve covers. If you want an idea on what it's worth, go to Facebook marketplace and see what other 350's of that era are going for. Most people looking for a SBC to build are looking for a block that's roller cam ready. Your flat tapped, 2 bolt main block isn't desirable. The cast valve covers are probably worth more (if you have them) than the rest of that long block.
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From: At my Bar drinking and wrenching in Lafayette Colorado
It's not an L81. Based on the engine ID ("ZAK"), it's a 1980 engine, so it's an L48 without the feedback carb and without the electronic spark timing. The base L48 just had the painted, corporate blue stamped steel valve covers. But it is a Corvette engine....
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Melting Slicks
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From: Fleming Island, FL
We can't assume what the OP has as he hasn't posted any pictures. It's possible in that 45 years of that engines existence it was swapped in a 81 Corvette with the rest of that engines peripherals and later the engine was removed from that 81 Corvette and was than considered an L81.
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
Marc -
OP says the engine is stamped with the "ZAK" code. That code was used one year only. It's a 1980 L48. A ZAK is not an L81.
The OP also stated that the last digits of the vehicle VIN number on the block are "AS431318". That "AS" stands for 1980 built in St. Louis. If it were a 1981, it would be "BS."
Absolutely, positively a 1980 L48.
OP says the engine is stamped with the "ZAK" code. That code was used one year only. It's a 1980 L48. A ZAK is not an L81.
The OP also stated that the last digits of the vehicle VIN number on the block are "AS431318". That "AS" stands for 1980 built in St. Louis. If it were a 1981, it would be "BS."
Absolutely, positively a 1980 L48.
Last edited by lars; Oct 27, 2025 at 09:43 PM.
Melting Slicks
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From: Fleming Island, FL
I realize all of that. The OP doesn't know what he's got and I don't think he even cares. He probably assumed he's got something special and his only thought is what he can get for it. I'm just pointing out that that engine is no different than most other 350's of the era so who cares where it came from or the year. And speaking of where it came from and this is for the OP do you know where that engine came from? Because if you sell it and the PoPo comes knocking on your door, telling them that it fell out of the sky ain't going to cut it. As a former brooklynite, stolen 350s were all over the place.
Last edited by Fly skids up!; Oct 27, 2025 at 04:10 PM.
Drifting
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So, it's a base L48 which was born mated to an auto trans in an '80 vette. Like an L81 OR L83; thin crack-prone heads w/ small valves + cast crank.
it's still just another worn ho-hum smog-slug base 350; That is, Unless someone needs a close match for their base auto '80.
with that "pedigree" doubt it'll rate any grand larceny hot sheet.
it's still just another worn ho-hum smog-slug base 350; That is, Unless someone needs a close match for their base auto '80.
with that "pedigree" doubt it'll rate any grand larceny hot sheet.
Last edited by Rebelyell; Oct 27, 2025 at 04:04 PM.
Race Director
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From: Virginia
@lars is absolutely correct.
If folks need a picture if an 80 L48 stamp pad with a partial VIN, I can go get one.
Suffix "ZAK" is a 1980 L48 automatic, Corvette engine, federal emissions. It cannot be anything else. It is a unique entry in the Lime Book, so you don't even need the partial 1980 Corvette VIN to clinch it.
https://corvettec3.ca/engines.htm
https://corvettec3.ca/vin.htm
https://www.camaros.org/pdf/LimeBook.pdf
OP, with that VIN, get a copy of your dealer invoice from GM (email them at the link in my signature). And please post photos. Welcome to the Forum!
If folks need a picture if an 80 L48 stamp pad with a partial VIN, I can go get one.
Suffix "ZAK" is a 1980 L48 automatic, Corvette engine, federal emissions. It cannot be anything else. It is a unique entry in the Lime Book, so you don't even need the partial 1980 Corvette VIN to clinch it.
https://corvettec3.ca/engines.htm
https://corvettec3.ca/vin.htm
https://www.camaros.org/pdf/LimeBook.pdf
OP, with that VIN, get a copy of your dealer invoice from GM (email them at the link in my signature). And please post photos. Welcome to the Forum!
Melting Slicks
Joined: Apr 2021
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From: Minnesota
I didn’t actually read the VIN. Looking at it now it definitely doesn’t match a 1981.
I would put it up for sale somewhere for a grand. If someone bargains you down to half that you’ve gotten your moneys worth.
I would put it up for sale somewhere for a grand. If someone bargains you down to half that you’ve gotten your moneys worth.
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
Thread Starter
3rd Gear
Joined: Oct 2025
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That's not a 1981 Corvette VIN.
1981 Corvette VINs are in this format and range:
1G1AY8764BS400001 – 1G1AY8764BS431611 (Cars built in St. Louis)
1G1AY8764B5100001 – 1G1AY8764B5108995 (Cars built in Bowling Green)
ID numbers starting with "VO" are engine ID numbers - not VIN numbers. The engine ID stamp pad will have both engine ID numbers and a partial VIN number, which is usually the last 9 digits of the vehicle's VIN. If the "AS431313" is the partial VIN, it is not a 1981 Vette engine.
The "V" indicates the engine was built in Flint Michigan. "0515" indicates that it was built May 15th. "ZAK" is a 1980 350 Corvette 190 horse engine with 4-barrel carb and a turbo 350 tranny.
Lars
1981 Corvette VINs are in this format and range:
1G1AY8764BS400001 – 1G1AY8764BS431611 (Cars built in St. Louis)
1G1AY8764B5100001 – 1G1AY8764B5108995 (Cars built in Bowling Green)
ID numbers starting with "VO" are engine ID numbers - not VIN numbers. The engine ID stamp pad will have both engine ID numbers and a partial VIN number, which is usually the last 9 digits of the vehicle's VIN. If the "AS431313" is the partial VIN, it is not a 1981 Vette engine.
The "V" indicates the engine was built in Flint Michigan. "0515" indicates that it was built May 15th. "ZAK" is a 1980 350 Corvette 190 horse engine with 4-barrel carb and a turbo 350 tranny.
Lars
Thread Starter
3rd Gear
Joined: Oct 2025
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I realize all of that. The OP doesn't know what he's got and I don't think he even cares. He probably assumed he's got something special and his only thought is what he can get for it. I'm just pointing out that that engine is no different than most other 350's of the era so who cares where it came from or the year. And speaking of where it came from and this is for the OP do you know where that engine came from? Because if you sell it and the PoPo comes knocking on your door, telling them that it fell out of the sky ain't going to cut it. As a former brooklynite, stolen 350s were all over the place.
Race Director
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From: Virginia
Thank you for kindly explaining this too me, the engine was left in the house I bought and I wanted to learn more about it- the neighbor said it was an 81 so I just assumed he was correct. I had no idea you could find so much out from just the VIN number, thank you again
1Z878AS431318
Corvette, coupe, L48 engine, 1980, made in St. Louis, car 31318 made of 40614.
No other options possible in 1980 with the "ZAK" suffix.
I wonder what happened to it. Did they leave any other Corvette parts? I couldn't give away my 79 L48 engine for $200-. Hopefully you can do better. Sell it as a "Corvette" engine, and don't mention that it has a 2-bolt main, and some of the worst heads to ever appear on a Corvette.
Good luck!
Race Director
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From: Virginia
The Forum will probably delete the link, but here's an L48, with a TH350, for sale in CA for $500-.
https://www.facebook.com/marketplace...98768112791637
https://www.facebook.com/marketplace...98768112791637
Drifting
Joined: Jun 2025
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Thank you for kindly explaining this too me, the engine was left in the house I bought and I wanted to learn more about it- the neighbor said it was an 81 so I just assumed he was correct. I had no idea you could find so much out from just the VIN number, thank you again
Kinda like an old, but mediocre at best, spinet piano. Not hankerin' for one of those either.