This is just my opinion , but sounds like it might be to much carb for the motors . There is a mathematical equation ( max rpm times Cubic inch divided by 3465 ) I think gives you cfm and then small adjustments from there I ran a 750dominator on a 10:1 468 big valves heads and about 600* of lift with smaller jets and ran great . Like I said just my opinion . Good luck guys !   


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Clean set up but I all ready got new carb / manifold . Bummer


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i have that carb and a killer intake for it that I'm looking to get rid of

Sounds like there is another issue.  A larger carb will soften the booster signal (less fuel flow) and a smaller carb will increase the booster signal (more fuel flow).  A larger carb will need more jet to make up for that lack of booster signal, not because there is more air flowing through the carb.  This is also complicated by the choice of a single plane or dual plane intake.  In a single plane intake, each cylinder draws from all venturi and therefore booster signal is reduced because airflow is shared.  In a dual plane intake, each cylinder draws through only half of the venturi and booster signal is much stronger.  This example compares single vs. dual plane intakes on the same engine with the same carb.  Jets will need to be sized accordingly.

If the carb is too small, it will limit peak HP.