If you bought the 318 with the carter BBD 2 BBL carburetor it might be the problem. Currently you can’t get good replacement accelerator pumps and we chucked them for 2 BBL Hollys and VOILA no dead spots in acceleration.
For those who like modernizing old carburetor cars to use fuel injection, we bought a kit from Mallory (I believe). A throttle body fuel injector an electronic ignition distributor and s brain to connect the two....also an 02 sensor so you must drill and tap the exhaust. The 72 Grand Torino, 350 Cleveland, starts right up ....you can drive without warming and there is never a hesitation and the power curve is incredible.
What about MPG?
My last project truck was a built 400 (.040 over). There was nothing Cleveland related in the injection market in a bolt on at the time. I wish I had that truck injected. It has ported 2V heads, oversize valves, a boss 351 spec hydraulic cam, ported intake manifold and a 670 Vac secondary carb with all the off-road mods. -Great- power and over 15 mpg highway. But it gets thirsty around town.