Gas
I had an 11 ran and ran the Non eth plug most all the time. I how ever made it a point to always buy gas from a station that was getting fresh gas 2-3 times a week. Had no ill effects in 1400ish mi. The only time I would run the eth plug was if I didn't trust the gas, like on a trip some where.
I also know that basic math says if you were to run a 50/50 mix, of say 87oct 10%eth gas, mixed with 104 non eth race. you would be in the 94-95 oct range with a 5%eth. would think that this mix would be way over kill to run you sled with the non eth plug. Even mixing 91 non eth 50/50 with 91 10% eth would more than be good if it is fresh gas.
The biggest problem with eth gas, is that the shelf life is only like 11days before it starts to head south. Now if your constantly putting fresh tanks of gas in more frequently than that, it should be more than fine. I alway put my sled away empty as I can get it, and run some stabil through it right before i park it. I do the same with my Boats 60hp outboard, and have never had a problem.
My father is a Still/small engine mech, and is a crazy when it comes to gas in stuff. one of the biggest things they teach at the Still workshops is how to manage the fuel problems. It is the number 1 thing he fixes on the weekend worrior's saws and weed whips. The guy comes in with the story, it ran great last fall, now it wont start. Empty the gas, install a new carb, put in new gas, right back to 1 pull technology. Good fuel is your friend, eth is not a problem, if you know what ya got to start with.
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