One reason for more power is that u could run an implment fast. And if u did idle it down, why would it use the same amount of fuel. My neighbor has an oliver 88 that is crankin OVER 200hp. It is a pullin tractor but has origlan rear ends and i think trany. If that can with stand that...with all of our inproved enginerin skills, think what tractors that have 200 hp can do. I am be wrong on this but doen't the 8100 have the same rear ends, trany and moter pretty much. So if it is the same as a 8400 except for a chip that tells it how much hp to put. And the sts are pretty much the same aren't they. So buy a 9650 and put the chip in it to make it the same as a 9750. Same goes for 9000 tractors. look at all the 4 wd tractors with DMI and Kinze repower. My 2cents