The V8 Owners Forum -

Fitted an Edelbrock 500CFM carb with electric choke. On cold start the idle speed is 3,000 rpm, so I want to reduce this. Which is the correct screw to use ? I think it's the one just above the left hand of the throttle spring with a red arrow in the pic below.

The blue arrow points to where the idle speed screw is which you can't see, but I know that's the right screw and have set the idle speed when warmed up to about 900rpm which is fine.

Just want to be sure before I play around. What should the idle speed on the choke be and I guess 'undoing' the screw reduces the speed ???

Alex

You are correct, the red arrow screw is the fast idle screw, I'd try to get it to run at around 1000-1100 rpm but that's just my opinion. (Screwing it out slows down the fast idle).
The blue arrow screw is the main idle screw, set this at round 800-900 rpm...this will depend on the size of your engine and the cam fitted. Basically you can see and hear when you've gone too low.

By the way the edelbrock badly overfuels even a tuned RV8 to the point where you will start to damage the bores if you leave it on the standard settings. Changing the needles for 67-55 will get you in the right ball park.

Pete

sidecar wrote:You are correct, the red arrow screw is the fast idle screw, I'd try to get it to run at around 1000-1100 rpm but that's just my opinion. (Screwing it out slows down the fast idle).
The blue arrow screw is the main idle screw, set this at round 800-900 rpm...this will depend on the size of your engine and the cam fitted. Basically you can see and hear when you've gone too low.

By the way the edelbrock badly overfuels even a tuned RV8 to the point where you will start to damage the bores if you leave it on the standard settings. Changing the needles for 67-55 will get you in the right ball park.

Pete

I completely removed the choke mechanism from my Weber, as I just could not seem to get it so it ran at a decent rpm whilst warming up. It was either 2000, or none. Now I just give it a few good squirts with my foot, then keep it alive for a minute so it warms up and become 'self sustaining'

[/quote]
I completely removed the choke mechanism from my Weber, as I just could not seem to get it so it ran at a decent rpm whilst warming up. It was either 2000, or none. Now I just give it a few good squirts with my foot, then keep it alive for a minute so it warms up and become 'self sustaining' [/quote]

I've removed the choke flap so there is no choke, the mechanism is now just a fast idle on my car.