How to set fast idle cam on 71 holley carb

[Paul C.]

idlecam1.jpgidlecam3.jpgidlecam2.jpgidlecam4.jpgThis what mine looks like and is set at when the engine is completely cold. I have seen pictures of others and they aren't set in this position. Is this correct??If not, how do I set it correctly.
Thank you in advance for all your help and input.

[James G.]

Re: How to set fast idle cam on 71 holley carb

IF I walk out remove the A/C and look at the auto divorced choke on my cold carb without touching anything it looks nearly identical to your photos.

What happened while the engine cooled is the bimetallic spring put tension on the rod which you have the hair pin clip on.

So upon pushing the accelerator pedal to the floor without cranking the engine - the whitecam with the steps raises, after releasing the pedal the white cam keeps the accelerator from closing via the tab with the slot. - in your photo. -

IF you reach over with your hand and open the throttle once --- and the cam does not move --
Then the rod with the dogleg and the hairpin clip needs to be straightened slightly--- making it longer and exerting UPTENSION on the whitecam when cold.

If everything works as I stated meaning the whitecam is moving UP, however the car is not achieving a 2200 RPM fast idle, then the tab with the slot can be bent a hair using a screwdriver. a hair to the right will raise the fast idle ALOT.

If you changed the gasket height or any choke rods OR replaced the bimetallic spring the main thing you are dealing with is the ROD length. -

[David M.]

Re: How to set fast idle cam on 71 holley carb

James...excellent description!
Optional: A small dab of 30W oil on the various pivots keeps things moving smoothly. Repeat annually.

[Paul C.]

Re: How to set fast idle cam on 71 holley carb

James: WOW!! What a great explanation. I will get out in the garage in the next day or so and see what happens. Got to get propane for my heater---cold out. Again thank you!!! I will get back with the results.

[James G.]

Re: How to set fast idle cam on 71 holley carb

My technical writing professor would be proud!

[Mike E.]

[Paul C.]

Re: How to set fast idle cam on 71 holley carb

Let me see if I understand how this system is supposed to work.When the engine is cold: the spring is all the way out on the vacuum break; the choke rod is all the way up; the fast idle cam is on the bottom setting; and the choke is closed. As the engine warms up the vacuum spring retracts and the choke rod moves up and the choke opens. The idle cam doesn't move. It only moves if you rev the engine to release it. Therefore the idle won't drop unless you rev it? I thought the CEC plunger kept the idle up until it retracted. It retracts but the idle doesn't decrease because the idle cam hasn't moved. I'm missing something here?

[James G.]

Re: How to set fast idle cam on 71 holley carb

I had issues with that cam on my 30,000 mile 71 LT-1 also. Mine was an opposite problem. It didn’t come off high idle as the engine warmed up. A bit of exercising it with light apps of spray lubricant ultimately rectified the issue.

Mike,
Mine did the same when I was driving in the mountains a few months ago, thanks for thinking of that, I had put it out of my mind.
I hit it with a little silicone and worked it back and forth.