Aussie, there are a few other things you may want to check out,
1) there is a larger needle and seat available---supposed to be for racing---allows more fuel faster.
2) there are different floats available again allowing more fuel into the bowls
3) the wall between the primaries and secondaries has a fill hole---this hole can be enlarged (with pin drill bits) to allow faster filling of the secondary wells.
4) no more than 9PSI should be allowed for fuel pressure. The carb will not work right or maybe not even work. It has happened to me. High volume, but not high pressure.
5) the accelerator pump can be changed out to a 2 bbl pump allowing a "bigger shot" (this requires machining the housing to accomodate the larger pump)
6) there are different size jets, secondary rods, secondary rod hangers and hanger cams.
7) there is a small set screw under the right side of the air horn(this is where the choke normally hooks up to the primary butterflies) by adjusting this screw you adjust the tension thereby adjusting the opening timing of the primaries and can somewhat lessen the "bog" This can be adjusted even if the choke has been deleted.
don't "overcenter" the throttle blades. This will create an adverse air flow/fuel mixing situation.
9)if you were to use a pull fuel pump out of the tank then a fuel filter (steel canister-make sure the arrow points the right direction) and then a push pump that may help to solve the problem. Some guys we used to roundy-round race (IMCA modifies) with used this method and said they had very good results. This may be overkill but it still an idea.
a few of these may help in your quest for the running out of fuel problem and the others can possibly help you go faster, faster.
Also, if you can use a "cool can" that could help some.
The Q-jet can be a very good carb if modified correctly or just simply tuned correctly. A 650 CFM to 750 CFM carb (the Q-jet)is really quite alot of carb and can work very nicely for many differnet size engines, including a 383.
There have been alot of very good ideas here and all are worthy.
I wish you all the good luck possible and please keep us posted
You have an awesome lookin' car. Thanks for representin' down unda.
cheers jer