I posted a few weeks ago regarding high idle. The fast idle screw is set on the second notch on the choke cam. The idle screw isn't even touching the throttle. At 4° btc, she idles just under a 1000 rpms. Smog tried to tell me it needs to be at 8° btc and idle at 500 since my emmissions sticker is missing from under the hood. I took it to another smog shop and recomended getting a low pressure electric fuel pump (my motor is a 350 out of an 88 pickup) and a regulator with a return line to tank that runs off vacuum. The tech said that he has ran those set ups on one of his camaros because the fuel pressure would build up at idle.

 

Fuel presure does not cause high idle speed. If anything it wiil cause flooding and lower speed or stalling. Somehow too much air is getting into the engine. I am not a carb expert, but either there is a vacuum leak or the carb is messed up. What carb is on the engine?

 

The bold part is your fast idle problem. When the choke mechanism is working correctly, the fast ilde screw should be stepped off the last choke cam notch. Find out why your choke cam isn't rotating all the way to the open position (choke not opening all the way, linkage stuck), then your idle will drop and the linkage will be resting against the curb idle screw like it's supposed to. Poke that choke cam down out of the way with your finger or screwdriver, and you'll see what I'm talking about.
He has an Edelbrick carb by the way.

 

Edelbrock 1406. I did a rebuilt myself on it with edelbrock's kit. There instruction say to have the fast idle screw on the second step on the cam. Me elec. choke works. The cam moves rights out of the way when warm, and the choke is vertical. I might have to run a taller gasket for air cleaner. Its from the 88 pickup I pulled the motor and tranny from. Too tall but after smog, I'll put something that will fit under the hood.

 

Oh sorry 69. I didn't realise you quoted my last post.

 

Oh ok. The way you described made it sound like the fast idle was on the second step when warm.
Pull the distributor vacuum advance hose from the carb and plug the port with your finger, don't worry about the hose. If the idle drops noticeably, you have the advance hooked to the wrong port (manifold vacuum). Having it hooked to manifold vacuum will be advancing your timing at idle, which also speeds the idle up. For your application (smogged engine) the hose should be connected to the "timed" vacuum port, which is the one towards the bottom front, passenger side of the big PCV center vacuum port. Also make sure all other unused vacuum ports on the carb are plugged, or that will give you a fast idle too.

 

Gotcha. I must have flip flopped them when I had my brother hook them up. I also have a spark delay valve. Does the small end go towards the carb? Is it even worth it? Smog missed it and someone told me it was so the CAT dosen't burn up.

 

I bet that's it 69. When I pinched the egr and advance hose, I remembered it dropped. I'll let you know monday. I just moved and stored my Camaro at the old tow company. My dad's 69 C/20 isn't helpful for smog reference, neither is he.

 

*pinched hoses to set timing.

 

Not once have I ever experienced a timing or idle speed difference when disconnecting the vacuum advance hose from the timed port. Normally, there isn't vacuum at the timed port. The "disconnect advance hose before setting timing" instruction is a throwback to pre-smog days when the distributors were connected to manifold vacuum.