[tobluforu]

This is pretty much what Chris wrote, but more detailed. I did not write this, but added to it a tad. Its what I did to get my original stacks to idle perfectly......
Setting idle mixture & throttle body maintenance
It is assumed that your throttle bodies have been cleaned and intakes (throttle plate, air mixture and vacuum) are “surgically” clean. Regarding idle mixture tune-up, first turn the air correction screws on the throttle bodies fully closed, then back out exactly 21/2 turns. Then adjust the throttle stops by removing all the linkages and, one at a time, loosening each throttle bolt locking nut. Lightly push the throttle plate towards the fully closed position. Turn the throttle stop bolt to allow the throttle plate to close completely. When you get to the point where you have almost removed the bolt, the throttle plate will stick shut. Now screw the throttle bolt back to the point where the throttle plate no longer sticks shut. (This is rather critical as the throttle plate can be closed too far and stick, as engine temps increase and alter clearances). Now that you have the throttle stop bolt set to just keep the throttle plate from sticking, screw the throttle stop bolt another 3/4 turn in the direction that opens the plate. Check for free play by pushing lightly toward the stop. If all is OK, secure with the locking nut and repeat on remaining 5 throttles.
At this point the engine should start and run, but idle will be slow. Run for a while (until engine oil temp. is about 180 degrees +), then shut down and wait 15 mins for heat expansion, then restart engine.
Check each throttle with an air flow synchronizer to find the throttle with the lowest air flow. Adjust throttle stop bolt on this throttle to allow more air through throttle plate. Note: NEVER adjust the throttle plate for less air (closing the plate)!! Then adjust all six throttles up to identical air flow. Idle speed should now be close to spec. (circa 900rpm). Note that bad plugs, timing, MFI pump adjustment will affect these settings, so make sure all is well before attempting this balancing.
Next, with engine still running, adjust and reinstall the four throttle valve connecting levers to just keep the throttle arms on the stop bolts without changing the idle rpm. L & R throttle valve push rods should be as close as possible to 149.5mm and reinstalled. Car should now idle but idle mixture should be now checked.
Normally if the idle speed is low, you must determine whether the engine needs more fuel or air. There is an easy way to check this. Remove the injection pump control rod at the cross shaft end (the large metal tube linking both throttle bodies). Leave the other end attached to the MFI pump. Check all throttles are still at their idle stops, and then very slightly push the control rod open. This will inject more fuel into the engine.
Does the engine speed up? This means the pump is set too lean. Does the engine slow down and puff a little black smoke? This means the pump is set too rich. At perfect adjustment, pushing slightly on the control rod will cause the engine to initially increase revs a little then rapidly decrease. The MFI pump is adjusted @ 1000rpm for basic rich/lean with the main enrichment. Idle speed is adjusted with the idle enrichment and is only effective below 1000rpm.
Fine tuning can be achieved by turning all six air correction screws very slightly (1/16 turn for example) then rechecking with your air synchronizer to be sure they are all the same. Then recheck all linkages are lightly tight and ball sockets have Bosch ignition grease in them. Finally, check throttle pedal goes all the way down together with the MFI pump being at full throttle.