Thoughts on Aviation Fuel

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Al Bundy
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Thoughts on Aviation Fuel


Post by Al Bundy » 15 Aug 2016, 08:08

Anyone have any experience running aviation fuel in a vintage engine? My neighbors son dropped a fairly low mileage 390 from a '68 T-Bird in his truck and has been running av gas in it. Runs good, but I'm curious if there's any adverse effects from using it.
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Re: Thoughts on Aviation Fuel


Post by R Code » 15 Aug 2016, 08:55

Used to be leaded, and higher octane rating. I think most of it is low lead these days anyway, but still w/a higher octane rating than road fuels. Been a while since I worked at an airport.

Unless the engine is built to use that high octane, it's a waste of $, not to mention the time and effort to fill up at the airport (where it's prob. illegal to pump that into a private vehicle).
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Re: Thoughts on Aviation Fuel


Post by 93RGTE » 15 Aug 2016, 09:01

There has been a lot of discussion of Av Gas on the Boss 302 forum over the years, since those cars have such high compression engines. Naturally, people come down on both sides of the issue. My experience is that adding some 100 LL helps with detonation, but cuts down on power.

Good article on fuels here: (thanks, bosscougars)

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Re: Thoughts on Aviation Fuel


Post by cyclonelou » 15 Aug 2016, 09:56

When I could get it I ran 100 octane LL blue av gas in a 440 6 pack Superbird I had years ago. It ran like a scalded dog with no problems.
I believe LL means Low Lead when talking about aviation fuel. Yet for cars it's a "high lead" content. Whatever, you can bet you won't get a bad tank of av gas as it's really highly filtered more so than gas in the tanks at stations.

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Re: Thoughts on Aviation Fuel


Post by mo2872 » 15 Aug 2016, 14:02

Yes, the LL in 100LL stands for "low lead". Yes, it is illegal to pump it into anything other than an aircraft. That does not mean it can't/won't happen.

At $4.24-$5.83 per gallon here at KTUL, I'm sure as heck not going to buy it for my car. Spendy enough filling up the airplanes!
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Re: Thoughts on Aviation Fuel


Post by CatsRock » 15 Aug 2016, 15:31

Ive been running av-gas in my vert for almost as long as i've had it. My future plan is to run 50/50 av-gas / marine fuel (no ethanol). Since my vert is a weekend driver it can sit for a week or two without driving (rains every day in fl lol) No issues and Ive spoken to a couple of other classic car people at shows and they do the same.
I get mine at a sunoco station that has a specific island for av-gas and race fuel. The local airport will fill up private gas cans but they have to be metal ( I've heard from others in similar threads they don't suffer from that regulation).
Motor runs great and for a street cruiser it has plenty of pep for me. :smoke:
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Re: Thoughts on Aviation Fuel


Post by Royce » 15 Aug 2016, 16:00

Been using scrap Avgas in my cars for 30+ years. It is virtually identical chemically to Sunoco 102 octane gas that was available in the 1970's. Best gas that you can get! Especially when it is free........

Aviation gas 100 LL contains about 28 grams of TEL per gallon minimum. The octane is achieved through the use of that amount of TEL, and Iso Octane which is simply refined petroleum. In other words there is no ethanol and no additives to degrade and turn sour in your tank. As such it has excellent storage properties, and can be just fine after 12 months in the can or your car's tank. Airplanes have to operate from the Dead Sea airport in Israel up to perhaps 25000 feet for some high performance turbocharged aircraft, so the vapor properties are also excellent.
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Re: Thoughts on Aviation Fuel


Post by johnboy » 13 Feb 2017, 07:54

Never gassed at Petro Canada befotre this weekend. Seems they have regular (10% corn oil), mid level (5% corn oil) and for no ethanol: premium at 91 octane, AND super premium at 94 octane.

In case someone might be interested. I asked the clerk (in Gatineau) and she said all Petro Canada had 94 octane.
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Re: Thoughts on Aviation Fuel


Post by zman » 13 Feb 2017, 08:03

Ran it in my snowmobile back in the day for a radar run.
Didn't go any faster, smelled funny. IIRC it dropped a few mph. :oops:
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Re: Thoughts on Aviation Fuel


Post by Mike_B_SVT » 13 Feb 2017, 14:03

mo2872 wrote:
15 Aug 2016, 14:02
At $4.24-$5.83 per gallon here at KTUL, I'm sure as heck not going to buy it for my car. Spendy enough filling up the airplanes!
That's about what Pure / non-Ethanol gas runs around here. Spendy, for sure.
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