[Tom Vaught]

Here is a link from the Holley book my old Holley Boss wrote that has a lot of good info on the Holley Feed Back Carburetor, the Feed Back Control Solenoid, and pictures of the parts. It also has a cut-away achematic of how the fuel flows from the fuel bowl to the main jet wells and adds additional fuel there (along with the normal flow THRU the MAIN JETS. click on the "https" or the link will not work right.

https://books.google.com/books?id=Cl...ematic&f=false

The page numbers are at the bottom of the pages, (left or right side at the bottom).
You want pages 43 to page 46.

Post up if you have more questions.

The duty cycle solenoid moves up and down based on the control knob and adds fuel based on when the fuel circuit is open from the bowl to the main jet wells.

So you have "fixed" main jets and you can "change" main jetting on the fly by using the feedback solenoid to add the extra fuel that you want. I guy who I have posted about before was a "Messenger" for a bank system before all of the computer stuff.
This means he covertly carried a lot of cash (for a given bank to use in their business) vs using Armored Trucks.
Car was a 427 dual quad 68 Mustang with cable operated Exhaust dumps.

When he was traveling across the desert he could open the exhaust cut-outs and make more power but he also needed more fuel to the engine for the HP/speed he was trying to run. Cool desert air and high speed means larger carb jetting.

The Quarter Mile systems seems to get the job done for him.

Tom V.

ps He also carried two "sawed off double barrel" shotguns in the car to discourage robberies.