fuel injection probs- coupe gt

[Alan Pritchard]

well ive got my car back together, and fitted a second hand fuel injection
system which i stripped and cleaned to the best of my ability.  when i fired
the car up it ran badly and wouldnt idle. after a plug inspection, and
felling the manifold i determined that no 1 was bad, i checked the injector
out of the car and it let very little petrol through, so i swapped it for
one of my old ones, the car was better, to get it to idle better i had to
wind the screw out by 1.5 to 2 turns, all better now.  i then drove the car
home, it was perfect to 2 grand, then major flat spot/rough running, at 3250
it cleared and the car rocketed better than it ever had done before.
  when i checked the plugs before i also notice no3 seemed very wet.
my question ...... what happens at 2000-3250 revs that would make the car
undriveable, i considered leaning of no3 (i presume thats what the screws
are for by the injector take off points)  but thought it may be something
else ie. 6th injector...... aux air valve, or regulator.....
when i stripped the system i removed the gauze from the fuel distributor,.
and the one from the regulator.
any help/questionss would be great
thanx