I am sure its more than the ecm, injectors and throttle body. I assume compression is different, pistons, cams, and more. It would be an awesome machine if you could even get to 85hp, but at 60 it doesnt add up for me vs the old 800. Now I am looking at purely cost vs output. I realize the 900 is an all around better machine, but I picked up a nice 2010 Ranger Xp 800 LE for under 7K and I cant justify 14K for a 900 unless there is some potential for REAL HP gains.....