Classic/Antique Car Repair: 1964 dodge dart, slant six, dodge dart

Question
Dear expert. This vehicle has the 223 slant six. It has an entire new fuel
system from tank to intake. New distributor as well as plugs and wires.
Reads 120 pound throughout on compression reading. All grounds have
been checked and secured. Yet. It still runs sluggish. At an idle it's o k. In
a drive it is fine one moment and not the next. Any suggestions or help
would be a god sent at this point as I am running out of patience and
funds. Thanks. Will

Answer
If this is an automatic transmission it might be a defect in the torque converter. The one way clutch in the converter may be slipping causing the engine to bog down during acceleration. If the engine and components are ok as you say, this could be your problem. With the car in drive an your foot planted firmly on the brake and the transmission in drive, a tach connected to the engine should record 1400 RPM when the throttle is mashed to wide open. If it does not and the engine is in proper tune, then the converter is suspect.