Early 90's trucks engine cores had provisions for roller cam spider, but these were not machined at factory. In terms of block differences roller cam were introduced into car line engines in late eighties. To get there requires engine combination, fuel system and ECM tuning to take advantage of Vortec superior combustion chamber design and high velocity intake runners. While I would agree that roller cam has advantages, but a well configured, flat tappet cammed 350, with a tuned TBI induction system can easily deliver 300+HP with a flat torque curve. i would find a true vortec block and run a tbi intake and take advantage of the roller block and run a nice roller cam that wouldnt mess with the tbi to much. I believe all hes wanting to do is run the vortec heads in his tbi truck.
