Ok guys. I blew the motor on my 400ex. Pretty sure the guys before me just ragged the cap out of it and it was in the making. One of the piston skirts just exploded. I just sent the head to LASLEEVE to get bored up to a 426. I have a fmf slip on exhaust and a stage 2 hot cam. What else do I need to upgrade for the 426 to run the best? Do I have to get a new sleeve or could I still use old one if it's not too bad? New valves? Port and polish? And what compression? I'm going wiseco and run premium pump gas sometimes with octane booster. Sorry its so long. Thanks for the help.