Topic: 1966 K_GT on ebay

[CharlesTurner]

It's a nylon arm. Ford changed from a metal arm sometime in 1964-65. The diaphragms are different too.
I took a quick look at mine and between the garage and the computer, I don't see any difference except the inlet, I have a filter there.
Jim

Aware of the nylon arm.  Was referring to the rod that connected to the nylon arm from the secondary throttle shaft.  Looks like a spring being used on the carb pictured.

[J_Speegle]

Looks like they lost the arm to the secondary diaphragm.

That should provide some odd throttle response. Guess owner didn't have a wire coat hanger so they used a spring instead   

[jwc66k]

Aware of the nylon arm.  Was referring to the rod that connected to the nylon arm from the secondary throttle shaft.  Looks like a spring being used on the carb pictured.

The arm is what caught my eye between sips of "enhanced" coffee. The secondary arm is in the full secondary activated position - aka on all the time. The connecting rod is replaced with a spring to the arm that controls the secondary shaft (too much "enhancement" in their coffee), and the position of the upper portion of the cam indicates the plates are closed. If the primary shaft is fully activated, the secondary opens "manually", although I can't see tell how much (the position of the forward hole for the secondary activation rod is not set for this). Closing the secondary is also not clear, unless that add on arm is missing a spring.

It looks like the Autolite 4100 is rigged to operate like a double pumper? 

The original question - I think you may be correct, at least it is supposed to.
Jim

[J_Speegle]

It looks like the Autolite 4100 is rigged to operate like a double pumper? 

No IMHO just the opposite. The original arrangement does operate like a Holley double pumper. By adding the spring and eliminating the stroke of the rear pump you likely get a big flat hole in acceleration (when you get the rush of air but no fuel with it) I would think.

[jwc66k]

- eliminating the stroke of the rear pump

Rear pump?

No IMHO just the opposite.

Yup. 
There is a screw/nut added to the choke closed adjust arm (the right side of the "slider bar" attachment) with a hole drilled into the choke arm, and a second screw/nut on the slide part of the arm that appears to go to the secondary cam bar/plate of the secondary shaft, also to a drilled in hole. It may be that when the primary is almost wide open, the "slider bar" opens the secondary, the spring closes it. The "slider bar" looks machined. Is this an old JC Whitney kit?
To put it in perspective, I would not want one of these on my car.
Jim

[J_Speegle]

Rear pump?

Should be diaphram

 
........................ Is this an old JC Whitney kit?

Not from my recollection.