I am considering an engine upgrade. Current motor is an '07 TC, 96". I am thinking about a SE stage II install to 103". The kit I am looking at has 255 cams, big bore cylinders, big bore pistons (I already have a Heavy Breather intake) plus the heavy clutch spring. My question is, will I have to have any head work done? Is it worth doing this. For those of you that have made this mod, how much of a difference is there? What about going to 110"? Any feedback would be appreciated.