i have a 98 banshee with all the normal mods i am using klotz racing synthetic mix 32:1 race gas is hard to get where i live the gas station only has 91 octane but there is a small airport in my town that sells aviation gas to the dirt track racers it is about 100 or 102 octane is this gas ok to use thank you

 

most av gas is 100 low lead and this is the same a 109 octane auto gas. i used it for years in my 2 stroke bikes and quads. the density is different than car gas so you my have to rejet. read your plugs.

 

I've used AV Gas (100LL) for a couple years now without a problem. You will hear alot of people say that its junk, its meant for airplanes, it has this and that, bla bla bla. The fact remains that it is an excellent 2 stroke fuel.

Av Gas has an octane rating of about 106 octane, as well as having some additives that make it more resistant to detonation than most race gas. This allows higher timing advance and more compression. I run a +4 timing advancer, timed flywheel (+10 on bottom end) and 240 lbs of compression in my 250R on av gas.

Av Gas's anti detonation qualities are actually closer to methanol than race gas.

so yes, go for it!

 

No, Aviation fuel is not good for this application.

Think of it this way -- aviation fuel is designed to run at very high altitude, at very low temperatures, at a constant rpm.

None of these things happen when you're riding your quad.

Although some people can get away with running av gas because of a lower compression engine, av gas will cause overheating and detonation much sooner than it's octane rating would show.

A leaded race fuel has a lower flash point, and will help an engine run cooler.

The use of aviation fuel is an old wives tale, and although there are a few people out there who still believe it works, it's just not good stuff for a performance quad.

 

ahh yes, I knew this one lil point that I disagree with Pam would come up again [img]i/expressions/face-icon-small-smile.gif[/img]

Av Gas is not formulated to only run at a high altitude, this can be proven by the simple question of 'when does a planes engine have its most load on it?' thats right, at take off, at ground level.

While its true that Av Gas does slightly degrade throttle response, this can be counter acted by running more compression, which Av Gas does allow over most race fuels (in a 2 stroke, NOT a 4 stroke!) 4 strokes are a whole nother ballgame.

here's some great fuel information that MP Racing has posted on his site, who is also a big fan of Av Gas, in fact, if you'd like to ask questions regarding it, feel free to call him, he likes to talk [img]i/expressions/face-icon-small-wink.gif[/img]

MP Racing Fuel Info

 

Airplanes also use better than twice the fuel at low altitude than they use at cruising altitude. One reason is that the engine is tuned to run at higher elevations and colder tempatures. (sound familiar) Most engine builder's will not recommend aviation fuel. It is the question of using the proper stuff. Av gas might get the job done, but race fuel formulated for your application is just plain better.

 

a lot of engine builders dyno test with av gas because it is federal regulated and very consistant from gallon to gallon so they can compare engine to engine power output.

 

yes, thats also correct..av gas stays the same at all times, even from state to state.

anyways, its really up to you. You won't hurt anything by trying it. If you like, try a tank of Av Gas, then a tank of whatever race gas you like. then run what you like.

 

<< a lot of engine builders dyno test with av gas >>



who, where, what bikes? Show me the data.

Race fuel is also very consistent. In fact, if you're using VP or ELF, it's more consistent (because it's used in AMA racing).

This isn't an argument. For high performance engines, no true engine builder recommends avaiation fuel. There may be some garage mechanics out there who use it, but for those technicians who truly understand what fuel does and how it affects engine performance, even the thought of aviation fuel is laughable.

you can base your judgement on a few guys who have used it and been lucky, or you can call some shops - Give Alan at CT a call, or just about anyone who actually works on stuff -- mention aviation fuel -- you'll get an earfull.



<< which Av Gas does allow over most race fuels (in a 2 stroke, NOT a 4 stroke!) 4 strokes are a whole nother ballgame >>



What!!! Tell me the difference in how a two stroke utilizes fuel compared to a four stroke? Explain your theory as to why fuels react differently in these combustion chambers. Sorry, but once the valves are closed on a four stroke or the piston is past the ports on a two stroke, combustion occurs exactly the same way with either engine.

Also, race gas WILL allow higher compression than aviation fuel, higher octane = higher resistance to pre-ignition. Show me any data that even comes close to proving your points, please.

Sorry Dill, I normally wouldn't even respond to your theory on aviation fuel, everyone's allowed their own opinion, but when someone else's engine is at stake...

 

first off, I speak from personal experience. My bike detonates on 110 Torco with my timing set as I normall run it on av gas.

also, your statement about any true engine builder even thinking about it is false. There are many engine builders that actually RECOMMEND av gas. Because you do not does not mean its laughable. MP Racing in Oregon and Klemm Research are 2 such builders who have good names behind them.

I find it hard to believe there is a fuel more consistant than Av Gas, because Av Gas is federally regulated. Elf and VP are also probably very consistant, but I find it hard to argue that one is more than the other.

Like I mentioned before, feel free to call either of these builders and discuss Av Gas with them.

as far as 2 vs 4 stroke, it comes down to the 4 strokes usually utilizing a higher compression ratio. In these engines a fuel such as C14 would be better.

I don't believe anybodies engine is at stake here..my earlier suggestion to try both in sort of a blind fold test (jet each time accordingly and not know which is which) and try it. I've never been able to tell the difference in any of my machines. Throttle response is good, starting is easy (first kick) and compression is very good. I won't run another fuel unless its methanol.

454, give it a try. Your engine will run great if you jet it correctly. If you have any more questions about Av Gas, I can answer them off the board, feel free to email me.

Pete