Av Fuel

[firemediceric]

I may have a line on some aviation fuel for a real low price of < $1/gal.

This is fuel that has been drained off of the tanks in checking for water. I feel confident I can seperate any water out that may be in the fuel. My question is can this 100 octane Av fuel be used in a regular gasoline engine?

 

[tackleberry625]

You have to be careful what type of engine you are looking to run it in. If you don't mind taking a chance on burning the valves/rings/pistons, then knock your socks off. If I still had my 76 Camero with a blown 454, then I'd run it in a heart beat, but not in MY Tundra.

If you do use it, your valves would be squeaky clean after a little use.

 

[tom slick]

It might have a small amount of lead in it.

 

[firemediceric]

So maybe run it as a small percentage along with regular pump gasoline?

 

[edhackett]

100LL aviation fuel contains as much or more lead as the old leaded supreme in 1973. If this is a modern converter equipped car, any use of it will destroy your cat and O2 sensors in short order.

Ed

 

[firemediceric]

Thanks. That is the information that I was not finding anywhere else. I guess I'll have to let this bargain slide by.

 

[tackleberry625]

I would unless I had an older car (without emissions equipment)

 

[vacuum_6]

Originally Posted By: edhackett
100LL aviation fuel contains as much or more lead as the old leaded supreme in 1973. If this is a modern converter equipped car, any use of it will destroy your cat and O2 sensors in short order.

Ed


Got that right. Killed my O2 in one month. Plus 100 AV fuel is different then 100 octane pump gas. Meaning I ran 100 AV and got a lot of knock then ran 100 pump gas and no knock. I think it has to do with the way the AV fuel is designed, the elevation thing.

 

[gto78]

Avgas contains 5X the amount of lead as leaded automotive fuel. The lead is the reason for the 100 octane rating. It's designed for cold weather, high altitude, and requires a lean mixture to burn efficiently. It also has a lower BTU rating than regular auto fuel- which is the heart of our power source.

The engines it was designed for almost all run at a fixed ignition advance setting of either 20 or 25 degrees BTDC. Also, the engines it was designed for run at very low compression ratios in the range of 6.5:1 up to 8:1. Since the engines are air cooled, run at a consistent cruise RPM, air inlet temps are mostly freezing, the atmospheric pressure is low, and a few other odd working conditions, they came up with this fuel grade. The engine and fuel designers all have built in quite a few detonation preventatives with low BTU/high octane being one of them.

Anyways, knowing that I ran it in my track car a few times and noticed the my 1/4 mile times got slower. I rejetted the carb for an unusually lean mixture which made the car hard to drive without stalling when letting the clutch out. With the very lean mixture my 1/4 mile times got better, even better than pump gas, but not easy to drive on the street.