[tirefryer93]

Ok, I finally finished my Holley 670cfm conversion on my 1993 chevy 355. Holley makes these throttle bodies for 87-89 pickups, but the only difference is the TPS hookup. If anyone else has been wondering about the Holley on a newer 350 TBI, go for it. As I stated before in another thread, the TPS hookup is different on the newer 350s. But fortunately, the TPS clip (older style) is the same on 4.3s, 305, and 350s. So I took one off a 4.3 caprice. The wires (3) are color coded, so it is simply a cut-and-splice operation. The Holley also comes with wires that go to the injectors, but that is another simple project. One thing to consider, however, is the fact that the Holley's "adjustable" fuel pressure regulator is not very adjustable. The screw is so tight that it won't budge, and it's maxed out at 10psi (I have a gauge set up on mine). But upon looking at the Holley further, I realized that I could use a regular adjustable fuel pressure regulator for the stock TBIs. It simply bolts on top of the unit opposite the way the oem canister is. So, to sum everything up, I went from a stock throttle body ( 420 cfm, 55# injectors, 11 p.s.i. ) to the upgraded Holley ( 670 cfm, 68# injectors, 15 p.s.i. ). I am telling you right now, if you want more power, do this upgrade!