I had a friend ask me about getting some 238 hybrids and a 38r turbo on his 2000 f250 w/ 140k miles on it. Is that too much for a motor w/ that many miles on it? He says it runs great on his dptuner f5 chip, afe stg1 intake, and 4" turbo back exhaust just wanted some more power like mine but I dont have near that many miles so that I would ask around to those that may have more miles on their trucks w/ those mods.
If the motor is in good condition its perfectly fine. He will need some supporting mods as well. Fuel system, head studs would be a good idea as well as valve springs and push rods since you are in there.