ok my truck runs great right now an all but i've been reading up on the spark plug problem, and if it happend to me i'd like to go with a DOHC setup off of a Navigator to get a lil more power and also to make it a lil different, but how hard would it be? and would i need to change the intake and computer both?? i am however looking to make my truck a lil more powerful right now i have an exhaust dump right before the muffler but not sure if it's helping or hurting, so i'm putting on a Flowmaster with some Echo tips tommarow. but what else is there that is farily cheap(around 200bucks)

 

I am sure that you will have to at least change the computer, wiring harness, intake manifold, Timing chain assemblies and covers, possibly exhaust manifolds too. Air intake plumbing. Etc.
Jimmy