Idle speed too high

[stevef]

I've looked at other threads but cannot find my answer. My engine after rebuild is idling at 1500 rpm. The throttle levers on the webers are backed right off so the levers are resting on the carb housings. Can't work out if this is a linkage issue or a mixture problem. Idle mixture screws are set at 1 turn out, air correction at 1 turn out. In or out doesn't seem to make a difference.

[T Bird]

Where are the throttle stop screws? Are they backed out all the way? If you suspect the linkage, pop the press rods off of the throttle arms and see if your idle speed drops. Could be the distributor. Too much advance at idle will speed the engine. Have you checked timing?

[stevef]

The idle screws are backed right off. Funny thing about the timing. When I first got the engine going after rings and a head rebuild it was blowing alot of smoke. It was idling at that time around 700-800 rpm, I confirmed the timing at around 5' btdc at idle and 0 btdc static. As the smoke wore off the idle has been increasing. I assumed it might be because the compression has been getting better as the rings seat. I'll try disconnecting the press rods.