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Discussion Starter #1
Okay, so when i decide that i wanna haul ass, the truck goes. But when i start driving like a civilized person again, the truck starts to run like shit. I think that it is just loading up with fuel. It'll shoot some black smoke, but not too much. Are my mains too big? Secondaries opening too soon?
 

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Discussion Starter #2
Anyone? Truck really runs like shit, loads up at stop lights and barely moves. Once it gets to like 3000 rpm or so it evens out, but it used to run fine. Oh, and spark plugs are most definitley fouling. Once again, this was after a 1/2 throttle to 3/4 throttle run, nothing too serious.
 

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We need to know more info.

What engine, what carb, any modifications to either? black smoke from a gas motor is an obvious sign of too rich. But we can't help ya till we know specifics
 

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Discussion Starter #5
Chevy 350 Bored .030 over, 993 heads 75cc chambers, 1.94 int., 1.5 ex, stock exhaust, flat top pistons, Custom Cam .224/.224 Duration at .050 .467/.467 Lift on a 110* lsa, cam timing is straight up 0*, Edelbrock Perfromer RPM, HEI Distributor, Pertronix 8.5 MM Wires, Holley 600 CFM Vaccum Secondaries, AC Delco Plugs.

For the record, i cleaned out the plugs, ran really good for about a minute, than went to shit again. I have no idea, plugs are obviously just fouled, but i do not know why the engine would run rich at idle, because it has always ran fine until higher RPM. Idk much about whats in the carb, but the mains are #66, if that helps. Might just take it to the local guy, he's a fucking holley genius. Thanks for any help though guys
 

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Discussion Starter #6
Jet, rod size?

Might want to play with the carb mixture screws
Which ones? The ones on the metering block? Because if so, i thought that those were the Idle Mixture screws. please forgive me, im new with carbs.
 
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