Correct Fuel for a 327/365 SHP engine that is original

[Patrick P.]

What is the best fuel to use in an original 327/365 SHP 1965 corvette. Sunoco recommended mixing 110 race fuel with 50% Sunoco Hight test Are there any suggested formulas for keeping the car from pinging and causing valve wear
PT

[Larry E.]

Re: Correct Fuel for a 327/365 SHP engine that is original

What is the best fuel to use in an original 327/365 SHP 1965 corvette. Sunoco recommended mixing 110 race fuel with 50% Sunoco Hight test Are there any suggested formulas for keeping the car from pinging and causing valve wear
PT

Patrick:
From my experience for limited use there is nothing better then 100LL Av. Gas. You can buy it from any airport and pick it up in a
5 Gal can. It never turns sour like all other gas. It also has lead in it to protect the valves. I have use it for years w/o problems. Larry

[Michael W.]

Re: Correct Fuel for a 327/365 SHP engine that is original

No Corvette needs anything to prevent valve wear- that's an old myth. You'll find lots of discussion in the archives about the particular octane requirements of just about every engine config that GM fitted to these cars. There's very high probability that your car will run just fine on straight pump premium assuming it's in original configuration and is 'tuned' properly. If you do experience pinging, there's lots of well thought out strategies on how to deal with it without the need for 'racin' gas.

[Duke W.]

Re: Correct Fuel for a 327/365 SHP engine that is original

Most original vintage Corvette engines will operate detonation-free on available unleaded premium fuel, and no "lead" is needed for prevent valve seat recession unless you are road racing or towing 6000 pound trailers up over Loveland Pass.

What is the highest posted octane number available to you? Have you used it? Did the engine detonate?

Do you know how to convert PON to RON?

Any detonation experienced with the highest commonly available octane can usually be quelled with a bit of spark advance map tuning, but before you go looking for a "solution" you have to first establish that there is an actual problem.

Duke

[Paul J.]

Re: Correct Fuel for a 327/365 SHP engine that is original

Hello PT, welcome to the forum. This has been discussed a lot and you might wish to visit the archives. There is a lot of information there that will help, and further explains the information the others have posted.

Paul

[John D.]

Re: Correct Fuel for a 327/365 SHP engine that is original

Hi Patrick, Welcome aboard. It is great to have you.
In the old days I had a new 65 365HP. It absolutely loved 260 Sunoco as I recall. So did my new 66BB.
Listen to Larry's answer. Non I am not discounting MIkey from Canada's answer though. LOL. Especially since he is a fellow VH.

Info on 100LL. The more you cut it with crappy gas the less effective it is.
Google: pure-gas.org
Then click on your state and you may be able to find all the gas stations in your state that sell some decent fuel without ethanol. John

[Joe C.]

Re: Correct Fuel for a 327/365 SHP engine that is original

What is the best fuel to use in an original 327/365 SHP 1965 corvette. Sunoco recommended mixing 110 race fuel with 50% Sunoco Hight test Are there any suggested formulas for keeping the car from pinging and causing valve wear
PT

How many miles on the engine?
What is your static timing? Centrifugal advance? Vacuum advance?
Does the engine detonate?
Here are the factory timing specs for your engine: