I am trying to properly set up my 440EX and am worried about the deck height. I have been toying around with a compression ration calculator, but am still missing one of the numbers. I have a Wiseco piston with claimed 11:1 compression. It is looking like the compression is going to end up much lower than that. Does anybody have any idea what the CC amounts are for the valve relief pockets (should be a negative number?) and the dome volume of the piston (should be a positive number)? I know its super technical, but Wiseco has not been helpful getting me the numbers. They say, “If it is listed at 11:1 compression, then that’s what it will be.”

 

your having the same problem I came across...if anyone out their thinks that if they buy a wiseco piston 11:1 and they want that they better do their home work, first 11:1 it set up with cam in mind the quench volume valve job and head gasket, I had a local shop figure mine at 10:25 with no work done, after quenching the head, and jug, cam, valve work piston polished I was able to get close to 13:1 but I was very uptight putting it together two things will anything hit, 2nd will I blow a head gasket, I just put it together and started yesturday and everything is going good I can wheelie in first two gears with only throttle responce, it really has a good kick.