I was looking at performance parts for the kfx400 today and I found a 13.5:1 Weisco piston set for it. My question is would it have to run on race fuel? I think suzuki lists 11.3:1 as stock compresion. They say you can use 87 octane gas. When I bought mine I am sure that is what the dealer had put in the tank and I did not detect any pre-ignition knocks or rattles. I always run 93 in it anyway, even if it is not needed it smells better [img]i/expressions/face-icon-small-smile.gif[/img]. If 93 wouldn't do it could I get away with maybe mixing 1 gallon of 104 to 2 gallons of 93 or something like that? I would like the performance gains, but I can't afford to run pure race fuel all of the time. I also plan on adding a Big gun exhaust system, Hotcams stage 1 intake and exhaust cams. Ofcourse K&N filter, removal of the airbox lid and rejetting will be done as well. Any advice will be most welcomed.

Thanks