Aviation fuel in a drag car. OK or Bad idea?

Av gas is 80-100 up here in canada...piss poor fuel...Back in the early 80's we use to run 100-130 Av gas (green)
The blue 80 that they have now I wouldn't put in a lawnmower.

I don't know if it still applies,but when I researched this years ago I was told that "aviation fuel" has a much lower burn speed,because aviation engines turned at a slower r.p.m. than most race engines.
I don't know if all aviation fuel is even the same though?

High octane gas has a slower burn rate than regular gas. High octane fuel does not make more power. Running more octane than you need can produce less power.

My info came from Steve Burns, president of V.P. race fuels.He started out using aviation fuel,and decided to improve on it's properties.
I think this is one of the reasons he offers many different race fuels,not all engines need the slow burn,but still need high octane.

I've used lots my earlier days. 100 low lead is what I used.I use to mix a quart of tolulene to 5 gals of 100 LL. Under about 12:1 CR it worked for me.

ran it in many turbo cars with no problems including the race cars... Av Gas has an aditive in it to keep it from freezing.. No harm at all except to a car running o2's...

106 octane fuel... Per the guy that delivers it to our local airport...

Coutesy of V.P. racing fuels web site:

When Racing Gas got to be HIGH change to Avia fuel car has not miss a beat !!!!!! same Time as the C12.

Most av gas is 100 octane, they usually have lead and no lead. There is no highway tax on it, most airports would not let you drive a car up to the pump since that would be illegal.
Get in gas cans and tell them it is for a float plane. The down side is that it is usually more money than auto gas due to the limited competition . There isn't an airport on every corner to compete with.

As a guy who buys it by the tanker load I can clear up a couple but not all your questions. First, it's called 100LL. 100 being minimum octane rating. Second, LL means low lead which is a misnomer, it is actually a very high lead content which explains white exhaust pipes on airplanes(and the O2 comment above). There is no such thing as unleaded av gas in the US.....yet. The EPA is in the process of outlawing the tetra ethyl lead which will change a fuel that has not changed since Jimmy Doolittle got it produced. Av gas will soon be about 84? octane without lead but some other lubricating agents added. You can probably run it without problems if you don't mind the lead but keep it in mind while reading a plug.

If its a "race car" ..it should have "race fuel" designed for application

IMO

I'll just finish my two cents worth by saying that just because something works,that doesn't mean it works right.I wouldn't build a 20 thousand dollar engine just to look for the cheapest fuel to run in it.Just look at how many guys are looking for the "right" oil.

Because it cost less doesn`t mean it dont work!! some people on here buy 12.00 oil!! Ibuy 400 Dollar work just as good

I use to use avaition fuel in my race cars until I found all of the exhaust valves and seats pitted in my NHRA A/SA 1963 M.W. Belevedere, that was over thirty years ago when valves where cheaper. I have use race gas in my race motors every sense No burnt or pitted valves on race gas so far I owned a 1960 Piper Comanche airpalne for 15 yrs that had a 260 HP engine rated at 2700 RPM 540 C.I. air cooled opposed six cylinder in it, if I baby it at all it would lead foul spark plugs so I learned to lean the motor out as soon as it started and never let it loaf unless I was descending to land, I still kept the mixture fairly lean unless I was doing what is referred to as a go around and you then go to full rich for max power and lean it out as soon as you reach 3000 ft. above seal level. Avaition gas is design and made for slow turning low compression (8.5 or lees) air cooled engine, not high compression high revving race motors, avaition gas also has additives to give it a long shelf life as a lot of general avaition airplanes sit a lot between flights the specific gravity of most batches of 100 LL is around or under .690, most good race gas is higher than that

Whether or not avgas is suitable for a race car depends on the car/combo. If your combo's requirement exceeds the octane rating of avgas it's not suitable, for others it is.

back in the early 90's i bought into a curcuit car. on our first major closed street curcuit race during qualifying we noticed our car was slower than similarly spec'd cars. it was the car not my driving! a lil investigation found the gas we were using was av gas(supplied by crew member). one of the big name racers had a lab of sorts in his trailer, so we took him a sample of our fuel. a qwik test confirmed our problem. "it's av gas" he said, "get rid of it". he showed us in a glass capillary 3 different components of our fuel make up. burnable octane @ the top was the good stuff, below that was the additives for carb icing for flying high alt's(this doesn't burn btw) at the bottom was water(fuel is hydroscopic{absorbs water}) fuel from airfields thats kept in underground tanks absorbs moisture & the octane boils off in the heat of the day. ever since i only buy proper racegas in a sealed drum. can't make gobs of power if 15% of your fuel mix don't burn!

i'm no fuel expert John, i was only going by what i saw & was told. we ditched the av gas, bought a sealed drum of race gas, put that in the tank & we were instantly at the front of the field, no other changes. i only use fuel from sealed drums from that day on.

I was close to choosing AVgas testing as a senior project for school this past week, simply because it's ALWAYS a debate when someone brings it up yet NO ONE has any REAL data other than here-say and conjecture.

Since I didn't choose it for my project, here's my here-say and conjecture . It's rated at 100 RON, i've NEVER seen any MON data, also i've HEARD the way the RON test is done is DIFFERENT than the one done for vehicles. I've HEARD it actually has better storage properties than race fuel, octane does not degrade nearly as fast since planes stay on tarmacs for extended amounts of time...

My car has gone 8.0's with it with the assistance of some methanol cooling, how much it contributed to octane is unknown.

It's not all here-say and conjecture, there have been dyno charts posted in the past showing no appreciable difference between avgas and race gas with that particular motor.

Again, avgas is not appropriate for some circumstances.

Mopars Rule try it , it's your choice, you may like it ! I've ran it for a number of years in my mopars from 11.5 compression to 13.5 C.R. and had no problems at all , but be aware you'll have to jet higher with the av gas. I acquired an MSDS a few years ago and the properties are real close to 110 race fuel. It was 100 Low lead.

I don't know about all the scientific stuff but I ran 100LL in my dragster it was 14:1 copression and I used a 250 big shot plate on it also.Ran a best of 7.75@173mph no problems.