That series of carbs was designed to satisfy racer requests. Same quality that's expected of Holley, but with all the tunability of a custom carb. As said above, what's your combo, and what carb are you looking for?
410 ci c4 5500 stall with brake
makes about 550 - 600 NA
28" 4.56 gear
we ran a 850 stock with choke tower still on only re jetted for air. No other modifications were made. Looking to go to a real carb if you know what I mean. We have always used Pro Systems in the past but are curious about these new HP Ultra's. I think a 1000cfm 4150 would work well.
Talking to Patrick at Pro systems he recommends a 1000 cfm for the motor and rpm. I was thinking going with him or a 950 Holley HP Ultra. Don't you think a dominator would be way to much. I would be afraid the motor wouldn't be able to use all the dominator.
We just did a bunch of testing on a 358 with iron heads and a small roller cam. The engine made the most HP AND torque with a 1050 Dominator. Tuned right with the gear and converter you have it would run faster, and no reason the Ultra 850 or 950 won't work well either.