Hello , Please use caution with what i say here is Soley at your own Risk, should you wana try this :
Alternitives to Gas , is Alcohol

To Do this you need to make a Stilh . Most of the Engrediants are Free. Except Sugar , and yah if its done right dont think suger Sieze Engine, Sugar makes Alcohol.
What you need for a Cheap Stihl is a old Fountain pop Canister , Some Copper line , a Barrle , ICE and A Good Tourch / outside stove top.
You need to First make a Batch of Wine , you can get friut, Dandy lions , Or what ever suits your taste. to 45 gal barrle of wine add 30lbs Sugar, give it the real Kick. Add Yeast, let it sit and forment for about 2 weeks, than boil it down with stihl and you got Moonshine (alcohol) , if you wana make this to drink , make sure you clean your copper line with Vinigar & hot water well. 1 Barrle Boiled Down makes about 3 gals Shine , good for race , or to get drunk in a hurry.
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Another way to boost Power in a big way , is to add Mooth Balls to your gas, this works Better by far than octain booster , or Aviation fuel. And Yah it can add 50 more HP. Just becareful of how many you use , or you can Blow up in a fast way to.
Naptha Gas With Vitamane E , will also give you a good Punch

Make sure you Mix Vitamane E or Vedgtable Oil with it , or it Probly will melt your Pistons as it dose get hot. I perfer Vitamane E , as Vegtable Oil you smell like a french Fry truck.
these are just a few.. have fun
