Join Date: Apr 2002
Location: puntagorda fl u.s.
sbc 400 .40 over 10.5cmp dart pro1 heads howards solid roller cam 618-620 267-273 108 center mighty demon750 dartdual koolcan 6al msd current plugs are ac delco fr2ls. after replacing the #65 power valve witha 45 (only have 5-6 in vac) and tuning all day i still have a midly rich idle an black sooty plugs if i take the curb idle any leaner it stumbles and pops. what plugs would any of you suggest, the paper work with the heads recommends champion c59yc or rc12yc. to many plugs to choose from. thanks in advance