engine cutting out

I had this problem a few weeks ago and thought I had it fixed.
When crusing or taking off from a stand-still the engine cuts out for a few moments then kicks back in with full force, sort of like,
it has trash in the fuel.
I've run it empty, refueled with the good stuff.
Replaced the fuel filter.
I've replaced a electronic temp sensor on the carb.
Adjusted the timing and carb.
Checked the wires, & replaced the dist. cap.
It runs good for a few days then starts acting up again.
Even had the shop run a engine test, but it looks good on paper.
It's a 302 4b gt hatchback

http://gallery.stangnet.net/showphoto.php?photo=1389&password=&sort=7&cat=all&page=1

Anybody got any ideas, I'm thinking I should drain the tank and lines and
flush the hole fuel system, then look at the fuel pump.

sorry about that

Should have been a "b" for 4 barrel carb, had the disp.cap replaced, vac lines checked and any bad ones replaced 4 weeks ago, new fuel filter 4 weeks ago, new temp sensor, 4 weeks ago, high oct. gas, timing checked, carb adjusted, basicaly had the shop give it a good once over, but it still boggs down, if its warm or cold, touring along or launching it down the line form light to light. !st gear or 5th gear, when it starts I push in the clutch and rev the engine a few times and its good to go for a while.................just don't know. All I can say is my lawn mower it the same thing, and I flushed the fuel system and it works fine now............guess I'll give that a try.