ok, im not a good GM guy so ive seen people talk about the 4.3L TB on the 3.1L and boring out the intake manifold. i have a spare manifold and want to wake this 91 4x4 3.1L up for a short term run. MIGHT do the 3.4L later if this frame is solid enough and then build this into another 4x4/trail rig. the 4x4 spacecab im building is soooooo clean i dont want to bang her up too much. I may also swap cabs and put my 2wd spacecab body on the 4wd standard cab (bob the bed heavy) frame and swap over all the LS goodies :drunken: . anyway, what do i need to do to the intake? just the opening where the TB sits? any other performance toys for the 3.1L? like a 2.8L performance cam, 1.6:1 roller rockers? not looking for much, just alittle more ummph off the line. idle to 3000. im GUESSING the 2.8L s10 motor is the same as the Isuzu 3.1L, right??? just stroked more but will a performance cam work???