1995 Ford Escort GT fuel problem

This is a dirt track car with 1.8 engine. We broke a fuel line a few weeks ago and
repaired it. Not sure if that's relevant but trying to give all details. Car fired up with no
hesitation at all. Idled fine but when revved, would bog a little until throttle was feathered
and warmed up the car. Then it was fine. Ran strong with no issues. However, every
time it was shut off would need feathering to accelerate smoothly at first. Then would
be fine. Last Saturday, When we started it, it still idled fine. When I attempted to rev
the engine it would cut out completely, backfire, and continue to do so. Let off and it
was fine at idle. With some feathering, it would finally rev up. During the feature, it did
this and got it smoothed out. Then in the front straight, while floored, it cut out
completely (a new thing) and died. It fired up after a few tries, ran poorly, then
smoothed out after feathering the throttle. The return fuel line had become seperated
and repaired it but still doing the same thing. I've replaced the Fuel Pump relay, the
Throttle Position Sensor, and MAF sensor. It still does it and now is a bit difficult to
start. Initially it seemed to run rich when first starting it but now seems to not be
getting fuel. Can't hook it up to a computer, as no check engine light etc. is on the car
due to dirt track rules. Can anyone help? Have to have this on the track Saturday. First
year racing, 8th in points for the season, and not accustomed to figuring this stuff out.
Any help would be appreciated.