Hot Rod Forum banner

holley 850 dp

  1. Anyone running an 850 dp on a ZZ502 BBC

    My ZZ 502 came with a Holley 870 Street Avenger with vacuum secondaries. The motor runs slightly rich and the secondaries show up occasionally at wot . I was thinking of downsizing to the Holley 850 Double Pumper for a better mixture and performance. This is a street car and so far...