I have a 03 F250 with the 6 liter poserstroke. Heads are not reworked yet but soon will be. Once that is done I'd like to throw a few mods in it.I have a cat back exhaust, AFE intake, and Diablo tuner (not installed at the moment). How much power can the 5 speed auto-transmission handle if I don't plan on towing?
Do you know what transmission you have? A ZF5 perhaps? I would say you are probably good up to about 350hp before you will have to start beefing it up. I would start looking into a stronger clutch and flywheel. That is more likely to fail while towing before the trans itself.
make sure you get longer head studs the 6.0's are famous for blowing them when programmers are on them as far as trany you should be fine with up to 425hp if you have a 5r110 trany and its best not to run the programmer at level 3 all the time also here is a web site that offers fun mods for powerstoke diesels. http://www.diperformancetransmissions.com/
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