View Poll Results: Methanol free 90 octane or methanol / gasoline 93 octane
Methanol free 90
16
64.00%
Methanol 93
9
36.00%
Multiple Choice Poll. Voters: 25. You may not vote on this poll
[C2] Fuel
Thread Starter
Instructor
Joined: Sep 2021
Posts: 123
Likes: 25
From: Harrisburg PA
Fuel
I have a ‘66 327/300hp with 99k miles. I’ve had varying fuel advice. Should I use methanol free with 90 octane or or 10% methanol with 93 octane? I am using a lead additive too
Pro
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From: Lower Jefferson
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Back when the 300 hp engine was in my car I ran Chevron Custom Supreme. No way would I run 87. The ethanol free 90 is worth trying. If no ping you’re good to go. Can’t easily get E zero gas out here where I’m at. Just 91 with 10% ethanol.
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From: Sitting in his Nowhere land Hanover Pa
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Race Director
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From: Central Arkansas
I ran ethanol 93 for years and then switched last year to non-ethanol 90 that started to be sold nearby. But, I stopped in earlier this week to put some gas in my 66 and after starting the pump noticed the pump now said non-ethanol 87. I was wondering why their sign that used to say non-ethanol premium was missing. So I shut off the pump and switched back to 93. My 12:1 aluminum head motor is reasonably tolerant of fuel but probably won’t like a straight diet of 87 octane. 
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Thread Starter
Instructor
Joined: Sep 2021
Posts: 123
Likes: 25
From: Harrisburg PA
I ran ethanol 93 for years and then switched last year to non-ethanol 90 that started to be sold nearby. But, I stopped in earlier this week to put some gas in my 66 and after starting the pump noticed the pump now said non-ethanol 87. I was wondering why their sign that used to say non-ethanol premium was missing. So I shut off the pump and switched back to 93. My 12:1 aluminum head motor is reasonably tolerant of fuel but probably won’t like a straight diet of 87 octane.
Team Owner
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From: Sitting in his Nowhere land Hanover Pa
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Racer
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Some areas offer several grades of non-ethanol "Recreational" fuel. In central Florida, we find "Rec 90" or "Rec 91", depending on the station. It's all that goes in the collector cars - including the 65 327/350 - and they run well with no issues. In Wisconsin, we have some stations that serve up both 87 and 90/91 in non-ethanol form. We buy the 87 for boats, MC, lawn care equipment, etc. if it's handy. In any case, avoid ethanol where ever possible. Keep in mind, too, that octane ratings are generally a minimum spec. I would try the 87 and see if you get any detonation or run on. You could always "juice it" with some 93, if needed... ;-)
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Race Director
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From: Central Arkansas
Some station lines/ brands tend to use a lower level of ethanol in their gas than others. I remember reading about that a few years ago. So it might be worthwhile to do a current search for typical ethanol content by brand of fuel and geographical location and check up on that.
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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Some station lines/ brands tend to use a lower level of ethanol in their gas than others. I remember reading about that a few years ago. So it might be worthwhile to do a current search for typical ethanol content by brand of fuel and geographical location and check up on that.
Team Owner
Joined: Feb 2003
Posts: 54,073
Likes: 9,398
From: Sitting in his Nowhere land Hanover Pa
2024 C2 of the Year Finalist - Unmodified
2015 C2 of Year Finalist
Team Owner
Joined: Feb 2003
Posts: 54,073
Likes: 9,398
From: Sitting in his Nowhere land Hanover Pa
2024 C2 of the Year Finalist - Unmodified
2015 C2 of Year Finalist