holley question
How does rev when not under load and in nuetral? Does it rev clean? Do you get a black cloud?
I agree that this combo needs much more converter and this may be difficult to work around.
You might want to try a 1.0" power valve but before that, have someone drive behind you and see if you get a black cloud on stumble from take-off.
Also, you may want to see if you can borrow a Mallory or MSD distributor and lock out the mechanical advance. You may need much more initial timing to get this combo to work at all on the street/strip.