1981 Corvette convert to previous years
Thread Starter
7th Gear
Joined: Dec 2023
Posts: 7
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1981 Corvette convert to previous years
Hi,
I have a 1981 Corvette C3, automatic. I replaced the original Q-Jet carburetor with an Edelbrock one. I want to convert it to a 1975-1980 setup, removing the computer. Now I need to buy a Delco distributor from the 1975-1980 models. What else do I need to install it properly? Do I also need to get a ingnition coil?
https://www.corvette-avenue.com/243-c3-allumage-moteur - this is the site where I'll buy all the parts, this link has some parts which I think are necessary.
https://www.corvette-avenue.com/c3-c...rock-2101.html - will I need this also ?
Respectfully,
Alex
I have a 1981 Corvette C3, automatic. I replaced the original Q-Jet carburetor with an Edelbrock one. I want to convert it to a 1975-1980 setup, removing the computer. Now I need to buy a Delco distributor from the 1975-1980 models. What else do I need to install it properly? Do I also need to get a ingnition coil?
https://www.corvette-avenue.com/243-c3-allumage-moteur - this is the site where I'll buy all the parts, this link has some parts which I think are necessary.
https://www.corvette-avenue.com/c3-c...rock-2101.html - will I need this also ?
Respectfully,
Alex
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
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Cruise-In VIII Veteran
I won't comment on the quality of the parts your using, or lack there of.
However, yes the 75-80 HEI distributor is all you need. It's a complete ign. system. You can reuse your plug wires if in good condition. You can reuse the distributor clamp.
you do NOT need to change your intake manifold unless the carburetor you purchased is a square bore carburetor.
Am pretty sure that thing is not square bore.so you should be OK.
However, yes the 75-80 HEI distributor is all you need. It's a complete ign. system. You can reuse your plug wires if in good condition. You can reuse the distributor clamp.
you do NOT need to change your intake manifold unless the carburetor you purchased is a square bore carburetor.
Am pretty sure that thing is not square bore.so you should be OK.
Race Director
Joined: Nov 2006
Posts: 13,248
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
Do you have any need over there to pass emissions?
If not, a fair few more recommendations. If you do need to pass emissions. I'll bow out.
If not, a fair few more recommendations. If you do need to pass emissions. I'll bow out.
Thread Starter
7th Gear
Joined: Dec 2023
Posts: 7
Likes: 0
I won't comment on the quality of the parts your using, or lack there of.
However, yes the 75-80 HEI distributor is all you need. It's a complete ign. system. You can reuse your plug wires if in good condition. You can reuse the distributor clamp.
you do NOT need to change your intake manifold unless the carburetor you purchased is a square bore carburetor.
Am pretty sure that thing is not square bore.so you should be OK.
However, yes the 75-80 HEI distributor is all you need. It's a complete ign. system. You can reuse your plug wires if in good condition. You can reuse the distributor clamp.
you do NOT need to change your intake manifold unless the carburetor you purchased is a square bore carburetor.
Am pretty sure that thing is not square bore.so you should be OK.
Last edited by AlexTheFirst; Apr 8, 2025 at 07:52 AM.
Burning Brakes
Joined: Dec 2017
Posts: 1,043
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2023 C3 of the Year Finalist - Modified
youre better off using a Qjet if you stay spread bore.
if you’re dead set on a square bore carb, I recommend changing the intake to match. Edelbrock 2101 is a very popular intake that fits under the hood.
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Joined: Mar 2017
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From: Virginia
There's nothing wrong with switching to a square-bore intake, especially if you can't find an 80-spec Q-Jet (and not a commercially rebuilt one, or "new"). But if you can, I'd return that Edelbrock carb and adapter. There are much better carb options.
And before you spring for a new intake, are you sure you aren't going to be replacing the heads and/or cam soon? Don't do stuff twice!
And before you spring for a new intake, are you sure you aren't going to be replacing the heads and/or cam soon? Don't do stuff twice!
Race Director
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I don't know a lot about Edlebrock carburetors other than Edlebrock should stick to what they are good at. They make decent heads. They make good intake manifolds. But there Carburetor is fashioned after a early 60's design that was abandoned back in the mid 60's.
Yes, get a nice aftermarket square bore intake manifold that deleates the EGR and the heat crossover.
Loose the air pump and all it lines. Get a good Holley carburetor. Put some long tube headers on it and proper duel exhaust.
Purchase a distributor from DUI. Not some cheap Chinese copy.
Now you'll be cooking.
Yes, get a nice aftermarket square bore intake manifold that deleates the EGR and the heat crossover.
Loose the air pump and all it lines. Get a good Holley carburetor. Put some long tube headers on it and proper duel exhaust.
Purchase a distributor from DUI. Not some cheap Chinese copy.
Now you'll be cooking.
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Old Pro Solo Guy
Joined: Dec 2017
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From: Marlton NJ
A good pre-computer control Q-Jet is your best carb. For streetability and gas mileage.
I mention that because I believe gas is fairly pricey overseas.
But Q Jets are hard to find, in good cond, and so are parts to fine-tune it if you move away from stock.
An Edelbrock AVS is an OK choice, and it can be fine-tuned, but they sure are different. It can give good mpg if done right, and you can still get parts for it.
A good Holley is the more common choice, they are easily tuned, and a lot of people know how to work with them. But they are probably the most difficult to get good MPG out of. They normally run rich at part throttle.
You should make a plan first to see how far you want to go. Real dual exhaust helps a lot on those cars.
So does a proper performance oriented distributor re-curve.
https://www.corvetteforum.com/forums...e-numbers.html
I mention that because I believe gas is fairly pricey overseas.
But Q Jets are hard to find, in good cond, and so are parts to fine-tune it if you move away from stock.
An Edelbrock AVS is an OK choice, and it can be fine-tuned, but they sure are different. It can give good mpg if done right, and you can still get parts for it.
A good Holley is the more common choice, they are easily tuned, and a lot of people know how to work with them. But they are probably the most difficult to get good MPG out of. They normally run rich at part throttle.
You should make a plan first to see how far you want to go. Real dual exhaust helps a lot on those cars.
So does a proper performance oriented distributor re-curve.
https://www.corvetteforum.com/forums...e-numbers.html