I just bought a brand new edelbrock 1406, on a 72 chevy c-10, 350, it seems to function good when I get the truck to start, it just gives me problems when I place the vehicle in a drive gear, then it bogs down, and isnt responsive at all, but in park or neutral, it is very responsive, I cant figure it out, but as far as yours, my friends truck was doing same, his problem was vaccum advance, replaced it and his truck screams now