High speed idle cam discussion duration. Turn the screw clockwise 14 of a turn at a time until the rpm starts to drop.
Replacing The Fast Idle Lever 2100
Fast idle cam adjustment. If necessary adjust the fast idle cam screw a until the alignment mark is centered on the lever roller. To get to the fast idle screw you have to open the throttle all the way and only then will you see it swing into view and be accessible. Unscrew the fast idle adjuster screw until it is clear of the stepped cam. Screw it in until it just touches the very bottom of the stepped cam not on any of the steps themselves. Then rotate it back slowly until the choke plate just comes closed. Back it off about one turn.
At that point you can go ahead and snug those screws back up and thats going to give you a good starting point to make adjustments from. You do not want to aggressively throttle the engine to get the fast idle to drop. Adjust by switching between each screw. Holley set up and adjust step by step duration. Make sure that the choke is fully open and the fast idle adjuster screw is resting on the very bottom of the stepped cam. How to adjust the choke and fast idle on holley carburetors holleyperformance.
Set the idle to specification. Turn the screw counter clockwise 14 of a turn. Start the engine and let it warm to operating temperature or do the repair after a few errands that you needed to run anyway. You cannot adjust the idle mixture if the idle speed is too fast. Slightly crack the throttle open unload the fast idle cam and turn the choke cap clockwise until you see the choke plate open. If the accelerator is moved slightly open the fast idle cam will drop a notch and move toward curb warm idle rpm.
Measure the clearance between the lever roller and the top of the fast idle cam using a feeler gauge. Now screw it in another 14 turn. As the engine warms up the choke spring tension will be reduced. Fast idle and choke has to be set with the engine cold so it can be a bit of a pain to get it right since you pretty well have let it cool completely off between adjustments.
Gallery of Fast Idle Cam Adjustment
