Technical NEED HELP: ford flathead wont run correctly

hello, this is chris's friend im in need of some help with this flathead had rebuilt and i installed in a truck. it will run fine on its own for a bit, i could hold the idle up and it would stay nice n steady and smooth. but as soon as i tried to put the engine under any kind of load it would get all out of wack like it was only firing on a few cylinders. ive replaced the plug wires, tried different ballast resistors, moved the timing back and forth, checked the vacuum line for leaks with starter fluid. anyway heres a video, wondering if anyone else has had this problem.
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also, the plugs, wires, cap and rotor are all new.

 

Does the carb seem to bog down when you rev it?

 

like if i hit the throttle fast? yeah it doesnt seem very responsive. also it likes to die if i push the choke in all the way. do you think it is all clogged up maybe?

the engine ran ok before so i guess i never really thought the carb would be an issue.

 

CONDENSOR!!!! Little brass cylinder in the side of the distributor. Very common problem with flatheads.

 

ill have to check that

 

What year flathead? What distributor is on it? Stock intake? Multicarb?

 

after looking its inside the distributor, i thought you mean on the side of the distributor like an old mallory. its a 1951 8RT truck flathead, stock everything, but T5 trans and suspension.

i changed the condenser with another new one i had laying around, ran a little better, but still not running right.

 

ok, well i messed with a few different things the carb and the vacuum and both didnt help. i had a theory that maybe i wasnt able to advance it enough(my timing light is broken, waiting for someone to come over with one) and my distributor is limited between the head and the speedway alternator bracket. so i moved all the plug wires one over on the cap and then pulled the dizzy all the way to the head. and what do you know! i can drive it! but the only issue is now i think its too advanced and has lots of popping out of the exhaust. so, i think what i need to do is either find a stock vacuum advance end so i can sneek it past the alt bracket a little, or notch the alt bracket, or both. wish i could buy a cap with a few degrees built in it......

 

DOH, nevermind that last post all i gotta do is take the dizzy out and move the gear over one tooth! this thing should be done in no time!

 

good luck on your flatty, I love them!!!