1980 C3 Corvette stock L82 automatic engine
Thread Starter
1st Gear
Joined: Mar 2022
Posts: 1
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1980 C3 Corvette stock L82 automatic engine
Hello, I am new to the vette world but very happy with my 1980 C3 with 38k original miles with original stock L82 automatic. However, I have to ask about what fuel to use. My mechanic and car enthusiast friends say put 93 in it to keep it cleaner and run longer. My original owners manual states 87. I have tried 87, 89, and 93 so far and have noticed no difference in the performance of the vette. The price is not a concern for me as much as keeping my vette running good for years to come. I seem to find all different kinds of answers so I thought I would ask what octane to use on corvetteforum.com. Thank you very much for the replies!
Advanced
Joined: Aug 2019
Posts: 53
Likes: 24
From: Indiana
There have been forum threads on this in the past. I know of no reason not to use the 87 octane recommended in the owner's manual for a stock engine at regular altitudes. Choosing the right octane is tied to the compression and detonation specs of the engine. If your engine is knocking, then higher octane is something to consider. Otherwise, I would save the money and stick with the lower priced 87 gas.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Run the cheapest there is.....it is 9 to 1 compression engine and no high fuel is required.
If you have not done it....I highly recommend the performance timing setting that is recommended on this forum for optimum performance, power and longevity. Your car sounds like it has never been touched and the GM timing settings are woefully retarded to the point where fuel economy and power suffers.....especially on an L-82.
The timing paper is available form our member Lars if you are interested.
Jebby
If you have not done it....I highly recommend the performance timing setting that is recommended on this forum for optimum performance, power and longevity. Your car sounds like it has never been touched and the GM timing settings are woefully retarded to the point where fuel economy and power suffers.....especially on an L-82.
The timing paper is available form our member Lars if you are interested.
Jebby
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
v8fastcars@msn.com i have an older copy but Lars cops an attytude if you use his papers that HE didn't send you.
Burning Brakes
Joined: Oct 2020
Posts: 1,149
Likes: 265
From: The frozen wastes...
Man... Gas is $7.50 a gallon here today. I'm looking for excuses to put cheaper gas in my car... not more expensive...
80 L82... excellent engine. Tune it properly, and put a real exhaust on it.
80 L82... excellent engine. Tune it properly, and put a real exhaust on it.
