I've read somewhere that high octane fuel like Sunoco ultra 94 contains no ethanol.Would this make it safe for use in a fiberglass tank?Any replies will be appreciated,Thanx,Bobby.

haven't heard anything about that, and for the extra cost you might as well replace the tank....

The higher octane fuel is intended for higher compression engines, in other words it's less combustable. I'd make sure it would even be a good idea for your engine before thinking of the tank.

-spence