11:1 compression

[ti-ex]

i am thinking about keeping the stoc bore and going to a 11:1 piston,with xr400 head gasket/well i have to run higher oct fuel?

[plkmonster2]

I would run 92 octane minimum. you may need to use higher if you go to sea level. Also, most piston kits measure the compression using the xr gaskets.

[DH400EX]

u can run 93, most ppl stop runnin 93 wit a 11:1, nething higher i think they go to 110.