carbed out

Hold on Mike.
That 73 Dart is a pretty heavy car for a 273.This type of combo; heavy car/small engine needs special tuning parameters..
It needs compression, inherent torque, torque-multiplication, and usually, a late opening or carefully timed secondary opening.
Let's start with a compression test.I have a sneaky suspicion somebody bolted all these goodies, including the cam onto a low-compression shortblock. In which case, you are kindof in trouble......So on to checking cylinder pressure. If it's under 110, you are more than kindof in trouble. But if it's up at 150 or better, that we can work with. This combo will not wake up until the compression is decent. I'd guess 165 would be a good number, down to 150ish. Between 140 to 120,she's gonna need some to plenty of help.

Then,let's start with transmission and rear gears. Ima gonna assume it's an auto with a stock TC (low RPM) stall and probably still has the 2.76s in it? If that's true, your carb and intake, are waaay too big. With 2.7s or 2.9s or maybe even 3.2s,that engine will want a 500carb or so, on a heated intake.Your carb and intake might work with 3.9s or better, but for sure will need a loose TC.
So, if you wanna keep that top-end, start over with a 2800TC (or better), and at least 3.55s, and rebuild that Carter.
Or put the 340-AVS top end on it, with the 340 TC, and at least 3.23s.
Or take about 600 pounds out of that car!, and still the 3.23s.
Or pull that cam outta there and start over.
Or, there is one other option. A spreadbore set-up,a 2400 minimum stall and 2.94s as a minimum.

And do yourself a favor; when you get to tuning, defeat the secondaries, and tune the front first.Get the primaries working, and the accelerator pump dialed in.Then drive it around as a 2bbl for like 500 miles, getting the timing and stuff worked out. After that's sorted, then start in on the secondaries.Any other way is just madness.When you defeat the secondaries, make absolutely sure that they cannot open or fail open; No way! There is almost nothing as scary as running up some guys tailpipe while simultaneously jamming on the brakes with both feet, and reaching for the kill switch! Don't even think about neutral.