Rough Idle - Edelbrock Intake

[Paul Cotton]

O.K. I have a pretty basic question, at least I think it is basic. I have a 440 motor with a Bullet cam, Holley carb, Edelbrock intake and MSD electronic ignition. When I first start the car, it runs really rough, you have to keep revving the motor to keep it running. Once it warms up, it behaves pretty well.

Here is my question. When I changed the intake and went with the Edelbrock, I could only find intake gaskets that blocked off the crossover ports, I wasn't able to find the ones that allowed the intake to heat up. So, can anyone tell me if this could be the cause of my rough idle, (I have adjusted the carb several times) and if so, do these crossover ports being blocked off make the much difference in keep the carb cooler?

Hopefully I have made my question clear.

Thanks for your input.

 

[Davefinan]

If you were talking about just in cold months…I’d say it’s possible that could cause slow warm ups

 

[Ranger16]

Assuming that you have the choke and fast idle properly adjusted, it sounds like the nature of the beast, somewhat normal for a carbureted IC engine. Mine take a minute or two to really stabilize.

 

[69 Sleeper Bee]

Have you looked at the choke plate to see what it is doing when you 1st crank it up cold. Choke may be set to tight when cold.

 

[4speed68rt]

Sounds about normal. Don't forget that a carburetor is a compromise of many different factors and unlike fuel injection its not able to constantly correct the mixture as it warms up. They are tuned for driving when it's at operating temperature.

 

[R413]

Do you have any choke functioning on it?

 

[66Satellite47]

I doubt the blocked heat passage has any real affect, except it may affect the choke setting.

 

[R413]

I bet the blocked intake does have an effect on the cold running of the engine, but there are many unanswered questions Here.

 

[toolmanmike]

O.K. I have a pretty basic question, at least I think it is basic. I have a 440 motor with a Bullet cam, Holley carb, Edelbrock intake and MSD electronic ignition. When I first start the car, it runs really rough, you have to keep revving the motor to keep it running. Once it warms up, it behaves pretty well.

Here is my question. When I changed the intake and went with the Edelbrock, I could only find intake gaskets that blocked off the crossover ports, I wasn't able to find the ones that allowed the intake to heat up. So, can anyone tell me if this could be the cause of my rough idle, (I have adjusted the carb several times) and if so, do these crossover ports being blocked off make the much difference in keep the carb cooler?

Hopefully I have made my question clear.

Thanks for your input.

Yes, yes, and yes. Does your Holley have a electric choke? You can richen it up so it stays partially on for longer if the rough running is an issue. I wouldn't worry about the heat passages being blocked off. In fact if you are still running

 

[Moparnocar]

I drill a 1/2 hole in the plates, quicker warm up

 

[gtxrt]

check for a vacuum leak, slowly block the air to carb make sure it stalls and the idle does not speed up.