09/75 fj-40 I-6cyl edelbrock headers (SOR mfg) mallory distributor weber 38mm DGES carburetor stock intake stock heads stock short block no emmissions systems except for the pcv valve etc. i have a 75 cruiser that i've been fighting with for about six months now and just can't seem to get the thing to run right. i just put a new mallory distributor in it, but that didn't seem to help much. i brought it into correct time and checked it with a timing light. the engine is in time. the mark jumps arround slightly, but it's barely enough to notice. one of the main things that i have found was the 5th and 6th cylinders were not firing inside the engine while at idle. once the engine would rev up, they would start to hit. i thought it may have been something with the dwell on the distributor, so i went to my local auto zone and bought a dwell meter. the book says, for that distributor, to bring the combined (dual points) dwell to ~40 degrees. it's at that... and the engine is in time, so i began looking at the carb and found out that the idler screw was in too far. once i began bringing it out, those two cylinders evened out and started running. that solved problem #1 the second (and most serious) problem is that the engine hesitates upon acceleration, and occasionally "pops"/backfires (it doesn't make a loud noise) both during acceleration and while the engine is at a higher, but steady rpm. i have kinda fixed this problem by bringing the choke in a little bit. if the choke is fully open, it will hesitate, but when partially closed, it runs fine, as long as the second barrel of the carb does not open. if that happens, the engine runs rough, misses, etc. with a sharp pop on the fuel pedal, it will rev up like it is supposed to, and the choke opens fully to allow for the flow of more air. at this point, there is no hesitation or missing, but, like i said, if the second barrel opens, it will miss. i am thinking there is something wrong with the fuel mixture. with the choke closed it is causing more of a vacuum on the upper part of the throttle body, thus causing more fuel to flow from the fuel boal. (increased richness) i think that the engine is not geting enough gas in the mixture, and when the second barrel opens, it throws the whole thing out of whack, increases the air in the ratio, and causes the engine to run lean. do any of you have any suggestions on what to do? does the carb need to be/can be tuned? anything at this point will help. further, i have checked the compression on all of the cylinders. they all hold as normal. i have checked and double checked the backlash of the valves. i know the distributor is installed in phase.