Holley 770 Questions

[Mattsvtcobra]

Originally Posted by MaSnaka

Do you have a mechanical timing advance on the distributor?? MSD. I noticed my RPMs were hanging up while lifting my foot. I cleaned and lubed the exterior of the carb (AED) and it would still happen occasionally. I had an epiphany and thought what if the mechanical timing on my distributor was hanging up. That would increase RPMs. So I popped the cap, everything looked good but I gave it a shot of wd40 where the weights and springs move. Problem gone so far. BTW- I have no vacuum advance on the distributor.

Hope this helps...
John

Gave mine a shot of wd-40 last night before bed per your suggestion. Just got back from taking my son to a friends house and we took the Cobra the RPM's increasing on me is gone! They fall back down to idle as they should. Thanks for replying and helping me!

Originally Posted by 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

When I took off the air cleaner, I noticed that the butterfly was open. The car has not been started for about a week. When I started your procedure, it closed and was up just a touch. Should the butterfly be open like that when the car is turned off?