Bill Oneal??????

[NITEHAWK]

I read somewhere here that you recomended the use of aviation fuel!! Thought that we were not suppose to use this in two stroke motors because of what it is designed for in use in high altitude??
Also then what is you opinion of the use of octane booster in these two stroke motors??
Thanks Kerry

[Bill O'Neal]

I cannot imagine what they would put into aviation fuel that would actually hurt a motor. I have always wondered how a can of fuel would know if it were in a two stroke or a four stroke motor [img]smile.gif[/img]

I have used aviation fuel in my own motors for years, and I have foriegn teams who specifically ask me to set their motors up for aviation fuel, because they have a tough time getting anything else with an elevated octane rating.

I never cared much for octane boosters as we have too many other options here in America. The one time I used it in Baja, I lost the head gaskets in my Ford truck.

[langford2000]

Hello all, I don't know if this would be a problem in these engines - but aircraft fuel does contain TEL (tetral ethyl lead) in concentrations of about four times that of the old leaded fuel that was once used in autos. I don't know about the deposits in the combustion chambers and the expansion pipes on these engines. Also the fuels other than 100LL (the blue stuff which is available at any airport) contains even more TEL used for the anti-knock needed for some of the older radial engines on vintage a/c. Also one other note is that avation fuel actually has two ratings such as the old 100/130 green fuel. They are rated that way because aircraft ALL aircraft pistion engines have a mixture control in the cockpit for the pilot to control the mixture - the higher # is for a full rich control and the lower # is for the lean mixture at altitude. Hope this helps.

[NITEHAWK]

Bill,
So what do you need to do to setup a motor to use av fuel?? What is different from just using pump gas??
Thanks Kerry

[mattgross]

jetting and compression

[NITEHAWK]

Like????????????????
Less compression and richer on the jetting??

[mattgross]

i think it would be high compression, and jetting witll be what it is, you will have to adjust that

[Bill O'Neal]

Do not go out and buy AV gas just to run AV gas..... If you need higher octane fuel, buy racing fuel or AV 100LL.

By need, I mean if you are suffering from pre-ignition (pinging) you probably need higher octane fuel, unless you have advanced your timing. Normally, you should not need a higher octane fuel unless you have raised the compression ratio.

[speedskier]

Bill,

I know you said you dont care for octane boosters, but I found this one product that claims to use TEL to increase the octane. It would seem to me that this would be an ok alternative, because isnt TEL the active ingredient in raising octane and would be better then the toulene that other products use. Its called Lead Supreme 130, the link to the manufacturers page is http://www.kemcooil.com/lead_supreme.php.

Whats your opinion on this? Seems that TEL would definitly raise the octane...

[Bill O'Neal]

Speedskier,
I looked at that product information for TEL additive. I guess if you could run it legally, it would enhance the octane, but I question the part that states "raises octane by 2 to 18 points". Does that mean a few ounces gets you 2 points and a quart gets you 18 points ? In how much fuel ? A gallon, 5 gallons?
At $120.00 per case of 12 quarts, plus the high price to ship a hazardous material $$$, I doubt that you would end up getting any more octane for your money than if you bought 96-100 octane fuel from a fuel distributor. And, you would still have leaded fuel, which is not allowed in any state waterway that I know of or the organized racing groups that we compete with.

It may have worked for my Ford truck in Baja though.....

Anyone considering using an octane booster should get an old carb diaphram and place it in a jar. Pour in the booster and let it set for a week or so, and go back a check to see if the booster has eaten away at the diaphram rubber.

I had a GSXL in my shop that I had to replace the pistons in, because the diaphrams were welded to the cover plates. I have to wonder what was put into that gas tank. I also have some real concerns about the fuel lines rotting.

[ March 04, 2003, 09:54 AM: Message edited by: Bill O'Neal ]

[speedskier]

**** I didnt realize it was illegal to use on the water. I was just hoping that I would still be able to fuel up at my local lake and not have to worry about wether the gas is truly 93 octane. And youre right if you do the numbers its not any cheaper then running av fuel or race fuel.

I have another question though, the closest place to get race fuel is about a 4 hour drive so I dont really want to do this more than once or twice a summer. How long will the fuel last in a 55 gallon drum? It would probably be mixed with fresh 93 octane every weekend.

Would the shelf life of av fuel be different or about the same?

[Bill O'Neal]

If you store fuel in a cool place with an air tight lid on the METAL can, or barrel, it will last for months. Eventually, it will lose a point or more of octane, but not right away.

I have a friend who carries Klotz octane additive in his skis, and he swears by it as an alternative when he buys gas at a marina. He normally runs racing fuel only. As far as I know, he hasn't had a problem, but he is smart enough to just use it to return to camp for a refueling of racing gas, without hammering his skis on the way back.

I carry a rope [img]smile.gif[/img]