How long will it take for fuel to break down in storage?

[chris406]

I've been using some Sunoco 114 that I bought from a friend. The gas was in a white plastic barrel definitely letting light in. The fuel had been sitting for over a year when I bought it. I was very hesitant about buying it, because I've always hated Sunoco fuel. The fuel stains things easily and smells like paint thinner. I run a carbed blowthrough set up I think the fuel bit me in the ass finally. At 26psi I think the fuel stopped working. My AFR was good at 11.0 but the plugs show detonation. Can fuel go bad and cause detonation?

[Pooch565]

Yes it can go bad. Plastic is the worst thing to store fuel in. If it is over a year old it is most likely bad. Not that it won't run, but the light ends of the fuel have evaporated off. I wouldn't run Sunoco 114 in a blowthrough anyways. It isn't a blower fuel. I would run C16. Anyway. A lined steel drum is the best way to store racing fuel. Just use plastic jugs for transfer from your drum to your car. Let me know if you have any other questions.

Thanks,
Jason