670 Street Avenger and Flat Cam Lobe

Start by replacing the power valves and then play with the idle mixture screws. They are supposed to have power valve blow out protection, but you never know. A 670 Is a pretty large carb for a 318 even with a big cam. I have one on my 355 sbc that makes 350 hp, and i feel its a bit too big. It does work better now that i swapped the gears from 3.08 to 3.55 that made a world of difference, and i had to re-jet and tune that carb again. I found i was too lean.