If your using the Edlebrock A.K.A. Webber try the following
I've had this problem also. Turns out that my idle was too high and I was trying to overcompensate with the mixture. start from the beginning. COMPLETELY close the valves, all the way. In fact make sure the idle screw isn't even touching the tang. Then set the mixtures two complete turns out. If you have the manual choke you can set it so it opens the valves slightly. Start the jeep, then as you turn off the choke increase the idle screw until you get the correct idle. Then fiddle with the mixtures. You may also want to double check the float level. I also use the off-road needles and I found the the float level needed to be adjusted more than what the book says. After I figured all that out it ran great.
Good luck
I've had this problem also. Turns out that my idle was too high and I was trying to overcompensate with the mixture. start from the beginning. COMPLETELY close the valves, all the way. In fact make sure the idle screw isn't even touching the tang. Then set the mixtures two complete turns out. If you have the manual choke you can set it so it opens the valves slightly. Start the jeep, then as you turn off the choke increase the idle screw until you get the correct idle. Then fiddle with the mixtures. You may also want to double check the float level. I also use the off-road needles and I found the the float level needed to be adjusted more than what the book says. After I figured all that out it ran great.
Good luck
