Holley 770 Questions

[Anthony]

Like gaz64 stated, I think it’s a fast idle cam issue. As your carburetor looks spotless, I don’t think the fast idle cam is binding. Maybe the spring in the choke housing has changed over time? Anyways, I think the choke needs adjusted, as the fast idle cam is connected to the choke linkage.

Here’s how I do it. The engine has to be cold. Take the air cleaner off. On the passenger side of the engine, Loosen the 3 screws on the perimeter of the choke housing, That are clamping the adjustment plate tight. Grab the throttle linkage and manually open to full throttle, and the choke should spring into the closed position. While holding the throttle fully open, with a standard screwdriver, adjust/ twist the loosened choke adjustment plate to where you see the choke plate start to open. I usually adjust it so there’s about a 1/4” gap between the edge of the choke plate and the carburetor housing, so the choke is almost, but not completely closed. Let off the throttle, and tighten the 3 choke plate hold down screws. See if that helps.

Regarding the engine bogging, pull the distributor cap and check for corrosion