Well I want to figure out what pistons to go with ahead of time because I want to get the head port and polish with new valves and guides and such plus the cams and cam gears before the bottom end goes in. The bottom end will probably be the last thing done. Is it fine to run the new cams and built head with stock pistons or would I need to do everything at one time? Also, on a side note, when you have an ecu programed can you reprogram it as many times as you want. I was going to get it done before all the head work was performed...then after and then one last time when everything was wrapped up since there will probably be a good amount of time between the head work and the bottom end being done.