Choke for dual quad FE

[DanEC]

This is a follow-up on my earlier post about dual quads on my FE. I would like to have a functioning choke system on the motor since all I need is a manual choke cable. Not having multiple carbs on any of my cars before I'm not sure if I need to only hook up the front carb, or hook up both carbs. I'm pretty sure all the old 3 x 2 setups on Pontiacs, Chevrolets, and Mopars only choked the center carb - but I don't thing the outer carbs had idle circuits. With the twin 1850 Holley carbs - both have idle circuits that are in operation. The front carb appears to require about 15 deg throttle opening before the back carb starts to open.

I'm thinking I will need to have both choke valves hooked up to have an effective choke and fast idle system. What do you think? (yes - I know I don't need to have a choke sysem but I like having one.)

thanks

[WildBill1965]

Choke on the first carb is all they used!

[Gaz64]

All dual four barrel intakes only run the choke mechanism on the "primary carb" if they are progressive.

You will find all progressive four barrels have the "primary carb" primary barrels as near as practically possible to the centre of the engine.

The whole engine breathes on this 15% of throttle.

[DanEC]

OK, front carb only - even though both carbs have idle circuits that are in play at idle.

This isn't like a 3 x 2 setup where only the center carb has an idle circuit.

[SuperHart]

As previously said, you only need the choke on the primary carb. The choke assembly and all associated parts can be removed from the secondary carb. Below is a photo of how I set my carbs up, a pair of Holley #8007 390 cfm 4160s. Using the manual choke arm from a Holley choke kit mounted upside down (because the carbs are mounted in reversed position) I secured the choke cable to the secondary carb vacuum pot assembly with the mounting clamp and then mounted the choke cable in the dashboard of the car. It works quite well and was a cinch to rig up. Even though my motor is a 351W the same thing would apply to a FE motor.

[DanEC]

I'll look at that method of reversing the choke lever. That would simplify hookup and routing of the cable.

Thanks

[SuperHart]

When I say "reversed", what I really meant is that I mounted the lever upside down from the usual position. The lever is not "turned around", just upside down. That way you still set the choke by pulling the cable knob out. I hope that's clear.

[DanEC]

Originally Posted by SuperHart

When I say "reversed", what I really meant is that I mounted the lever upside down from the usual position. The lever is not "turned around", just upside down. That way you still set the choke by pulling the cable knob out. I hope that's clear.

Yes, it was. Right now mine is set up where it will have to be pulled from the front to close the choke.

Thanks

[Jeff Frigo]

Why would you ever need a choke in Arkansas, are you kidding?

[DanEC]

Originally Posted by Jeff Frigo

Why would you ever need a choke in Arkansas, are you kidding?

With your being from Chicago I can see your point. I just like my engines to start once from cold and keep running versus several start/stall/restart cycles that washs the cylinder walls down with gas. And it's a tuning challenge to a choke/fast idle system set up to where it works properly. But no, I probably won't be venturing out in many sub-40 deg days.

[elmariachi]

Originally Posted by DanEC

I just like my engines to start once from cold and keep running versus several start/stall/restart cycles that washs the cylinder walls down with gas.

If anything a choke will exacerbate this because it intentionally creates a rich condition by blocking the primary airflow. If you have your carbs setup right, you should be able to start a 2x4 setup without a choke on the first couple of revolutions and get it up to 1300-1500 instantly and keep it there. I push the pedal to the floor twice, keeping it to the floor the second time and crank it. It fires instantly and doesn't struggle to run.

[ERA Chas]

X 2. That's how it works.

[Michael C Henry]

I tried to clean my emmissions up. My cruise hyco were almost with in limits but idle was allmost 11 times the limit. I had new metering plates prepaired for me. That cleaned up the idle. The garage was not as gassy at startup anylonger. Colder weather ( anything less than a warm summer day) starting was now a problem. I needed to put the choke system back . I had the choke towers cut off both carbs but had kept the fast idle cam that is used with a choke for warm up. So I had to get another carb main body with complete choke tower and put all my parts on that carb body.

[xlr8tr]

Originally Posted by elmariachi

If anything a choke will exacerbate this because it intentionally creates a rich condition by blocking the primary airflow. If you have your carbs setup right, you should be able to start a 2x4 setup without a choke on the first couple of revolutions and get it up to 1300-1500 instantly and keep it there. I push the pedal to the floor twice, keeping it to the floor the second time and crank it. It fires instantly and doesn't struggle to run.

My 2 X 4 setup starts fine, almost exactly the same process as you use when its warm outside (65+ degrees) but its a bastard when its colder than that...

[flaflier]

Pump it twice, turn the key, and she fires to life. Feather the throttle keeping it about 1300-1500 for 30sec to 1 min, then let her go.. of course I live in Central Florida, and it's mid 70's or warmer 98% of the time!