Originally posted by TUBJUB
i knew i was forgeting something. i have 5/8" headers and a holly 750 with vac. secondaries. the intake is the edlebrock rpm air-gap. if i left anything else out, please let me know and i will tell you. thanx
One thing you did not talk about was your fuel pump.Like everyone has said maybe your heads quit breathing.Most of the un-touched Vortec heads are done at the 450 h.p. area from what I have seen.