the old Motorcraft carb on the 67 has given me some trouble so i swapped it for a Holley that a buddy had sitting in his garage. i bolted the Holley up and the car ran great. i let the car sit for a few hours and i tried to crank it up. it took a LONG time for it to crank ( so long i wore the weak battery ran down and i needed a jump ) and when it did start, it idled really really bad and there was alot of black smoke coming out the exhaust. for some reason when i pressed the throttle, it would raise and stick about 1000rpm above idle and stay there for a few seconds before it settled back down to its regular idle. ( still really bad idle though ). i let it sit overnight and after work i messed with it more. the float on the front bowl ws high so i lowered it and the jets in it wer eway to big so i swapped them from teh 72's to some 65's that i had in the garage. fired it up, played with the idle screws a bit and it ran like a champ. it had a bit of a bog that reminded me of too light a spring in the vacuum secondaries. if i gassed it a bit and it still blew some smoke. after sittig for a few hours i went back out and it was hard to start again. it eventually fired and it ran rough again and if i gassed it, ALOT of smoke would come out the tailpipe. infact, so much smoke that my bro- in law who was smoking and the time started to choke lol. any ideas whats wrong with the carb? its a 600 Holley, vacuum secondaries with a manual choke thats disconnected. its on a289 as well. im probably gonna put the Motorcrap carb back on but that doesnt run so well either ( bogs off idle pretty bad ). someone told me that maybe the power valve? im lost lol. thoughts? suggestions? ridicule?