Where did you get your ross piston, and how much. Did the place where you got it tell you what kind of gas to use. What elevation are you riding at.

 

LDJ, i got my piston from CT Racing. I paid $125 for it. Allen told me that i didn't have to run 100 octane, but it would probably be safer to use it. Like i said, i used it for the first 5 or 6 tankfulls, then i went to premium pump with octane boost mixed in each tankfull.

 

Thanks for the info. I really want to get the 11:1 426, but after I bore it is there still enough sleeve left for cooling.