t_vanness
02-17-2004, 01:03 PM
I am looking at installing a 440 big bore on my 400ex and I just have a few questions for somebody. I cant decide on 11:1 compression or 12.5:1. Does the 12.5 to 1 piston cause a lot more heat and what jetting should I go to from stock. I ride at about 3000 to 4500 feet. Also would running race fuel/unleaded plus help any. Any help on this matter would really help. Thanks