1981 corvettes with L-82 engines

[Eric Roberts]

I am in the process of buying a 1981 corvette. The current owner claims it has an L-82 engine. I have tried to research this and have found a couple of sites stating that chevrolet installed these engines in some of the earlier production '81 models to deplete the stock. Can anyone provide any information on this? I have the VIN no. and have verified the car was made in St. Louis. I do not have the engine yet. Thanks.

[Mark Milner]

Re: 1981 corvettes with L-82 engines

All 1981 Corvettes came with a 190 hp L-81 engine. The L-82 was last used in 1980. It is possible for someone to swap engines, but it wasn't stock.

He could also be confused as to it being an L081 and thnking L-82.

[Joe L.]

Re: 1981 corvettes with L-82 engines

Eric-----

Very, very doubtful that an L-82 engine was ever originally installed in a 1981 Corvette. While, in some cases, previous year parts may have been "used up" at the beginning of the following model year, not for something like engines. The emissions certification requirements would make that virtually impossible.

Anyway, it's VERY easy to confirm this. Check the 8th digit of the VIN number. If it's a "6", then the engine is the L-81. This is the engine that was supposed to be installed in all 1981 Corvettes. If the 8th digit is a "6" (as I fully expect it will be), then the current owner is incorrect in his assertion that it's an L-82. Period.

[Eric Roberts]

Re: 1981 corvettes with L-82 engines

Thanks for your reply. You sound like you know what you're talking about.

I have verified the last 6 digits of the VIN with the 6 digits on the engine and they match. From what I understand that means this is the original motor installed in this car.

Also, there is another set of numbers above these on the block.
They are: V1027ZBD. From what I've been able to research, the ZBD indicates the L-82. Does that mean that this is indeed an L-82 engine? (Yes I'm sure this is the correct order of the engine code.)

Thanks, Eric

[Joe L.]

Re: 1981 corvettes with L-82 engines

Eric-----

"ZBD" is a suffix code used for 1980 Corvettes with L-82.

What is the complete VIN number of the car?

[Eric Roberts]

Re: 1981 corvettes with L-82 engines

VIN: 1G1AY8767BS409358

I've verified this number. I know the 6 is supposed to stand for the L81, but I've found a couple of websites that indicate that, although the 6 does stand for L81, since there apparently were some of the L82 motors used, this could also indicate an L82 motor. One website used 2 different decoding systems to decode the 81 VIN, because of the use of the L82 motor.

Thanks so much for your interest. I'll be eagerly waiting to see if you can shed some more light on this for me. Yes, I am excited... but cautiously excited.

Eric

[Michael W.]

V1027ZBD

If installed in a 1981 model year Corvette, this is a Flint built L-81 ( Not L-82) engine for California with automatic transmission. The engine was assembled on October 27th.

Nothing unusal about it.

[Eric Roberts]

Re: V1027ZBD

So why does the ZBD(not ZDB) indicate L82 in the decoding? just trying to figure this out. Thanks.

[Michael W.]

Re: 1981 corvettes with L-82 engines

This translates to 1981 car serial number 9038 which was built at St. Louis. Again, nothing unusual.

The '6' simply denotes a V8 engine with 4bbl, not the specific type or RPO.

[Michael W.]

Re: V1027ZBD

probable mis-stamp. Since there's no documented cases of L-82s in 1981, you've got a tough row to hoe to prove that's it's real.

[Mark Milner]

Things to check

Things to check:

1. Block casting date, located behind distributor on the bellhousing mounting flange

2. Pull a valve cover, measure the lift on an intake valve. The outside and two centers are exhaust, the others are intakes.

a. Roll the engine over by hand (wrench, etc.) until an intake valve is all the way up and the rocker arm is loose. Measure from top of valve to the head.

b. Leave the ruler there and roll the engine over by hand until the valve is all the way down. Measure from same top of valve to same spot on the head.

c. Subtract and get the intake valve lift. The L48 cam was .390 inch lift, the L82 cam was .450 lift. I believe the L81 cam was the same as the L48.

[Joe L.]

Re: 1981 corvettes with L-82 engines

Eric------

I'd guess that it's a factory mis-stamp as far as the engine suffix goes. I could see where the "D" and "B" could be easily transposed in the gang holder.

Another thing to check. Look at the harmonic balancer. Measure the approximate THICKNESS of the balancer (NOT including the pully mounted on the front). Report what you find.

[Eric Roberts]

Re: 1981 corvettes with L-82 engines

Joe, I actually had a mechanic that is very familiar with Corvette engines look at it last week. He also owns a car lot and has had several. One of the 1st things he commented on was the large size of the of the harmonic balancer common to L-82 engines. He also spoke about the unusual pistons the L-82 had in the engine which of course he could not look at. He felt certain it is a L-82, but nothing is impossible. I am going to buy the car regardless of the final outcome of this interesting story. The engine numbers match the VIN so to me that is the most important thing, the L-82 item would just be a bonus. I will still let you know what I find, I pick the car up tomorrow morning. Thanks for your help.

[Tom R.]

Re: 1981 corvettes with L-82 engines

No notes shows the ZBD as "uncertain usage" and I would be curious what the carb part number reads as well as the date code. And what is the broadcast code and part number of the emission sticker?