You have no idea if the F23 will make 250hp and neither does anyone else. It takes more than a crank swap to make power, in this case they used blox stg 2 cams and type-s or stock H22 pistons (I can't remember). Of course the F23 can't swap to a bigger crank, it has the biggest of the 4cyl's next to the K24 which uses I think a 100mm crank. But it could swap to the H22a4 or a7 crank for a little more rev happyness and a better R/S ratio.
When did the H23 or F22 enter this discussion?