Plenum was done also. Not a "max effort" but sure looks way different than it did before. VERY experienced guy. Did my heads also.
Honestly I'm sorry I bought that friggin Ulra XP carb. Way too much effort to get it close......fought it for 3 years. Now it's really close but.......I may be asking too much for a near 600 horse smallblock. I want the best of both worlds like anyone.
I think Holley created a piece of crap for such big money.
Think I'll take Turk's suggestion and get a Magnafuel anti reversion plate. His and others' prior tips is what finally got me almost there. My whole tune may change, but it might just help distribution.