[Tom Vaught]

A little Bit on "Pump Shooters" (since they were shown in the video - a Tech was changing one on the engine).

I like to remove the Pump Shooter parts off the car engine. (Takes no more that 10 minutes to remove the Holley carb completely from the engine.) I do this because it makes carb changes so much easier (on my back muscles) and fewer scratches on the fenders by helpers.

A Holley Shooter Assy has 4 basic parts:
The "Shooter", the Retaining "Shooter" Bolt, the gasket under the Retaining "Shooter" Bolt, and finally the gasket under the "Shooter" itself.

Now when you build the carb, you can glue the gasket under the "Shooter" to the Holley main body so it does not fall down on the Primary throttle blades when you are trying to install it or you can glue gaskets onto a bunch of Holley Shooters and then do the shooter swap like the Tech did in the video. I have a lot of Holley carbs and order parts for them but they only give you 4 shooter gaskets in a typical kit".
Two gaskets for under the shooter and two gaskets for the shooter retention screws (Double Pumper carb).
So I glue two of them on the carb main body when I have the choke shaft and blade out.

Shooters come in different sizes. .026", .028", .030", .031" etc. You can buy Shooter Kits that give you a whole bunch of them. When I worked for Holley I just bought a Cup Full of Shooters right from Holley of the smallest drilled size and then drilled them out for each application. If I drill one out and it is too much shooter volume too quickly then I put a smaller one in and put the modded shooter in the "square" in the box for the new drilled size. 40 Years later I still have a few small hole shooters left and have done a few carbs (lol) in that 40 years.
My shooters were the basic ones. Not "Shrouded" and not the "Extended Nozzle" type. The "Shrouded" nozzles were used on a lot of the 650 and 800 cfm Spread Bore Carbs. The "Extended Nozzle" were for specific applications but can't give you what they were off the top of my head.
Mostly aftermarket carbs.

The "Shrouded" Nozzle shooters were called "Anti-Pull over" shooters if you want to be correct on the name. Sometimes the air velocity past the shooter was strong enough that the shooter would see a slight vacuum and would pull some of the fuel out of the shooter. Not enough to pull fuel and raise the shooter 'check needle' but pull fuel from above the check needle.
The check needle is raised up off its seat by the pump diaphragm pushing fuel past it when the pump is depressed. I always take an old steel check needle and lightly make a proper seat around the Shooter nozzle hole inside the main body. Drop the old needle in the hole, insert a thin drift punch, set the punch on the steel needle, give it a light tap, and then turn over the carb and let the old steel check needle fall on a carb tray for use the next time. Now the gas above the check needle can't leak back to the fuel bowl.
If you have a metering block with a metered orifice on that circuit on the fuel metering block, it is there for a reason.
They put that orifice on some carbs as a anti-heat (fuel expansion) bleed if the pump diaphragm/housing is in a hot engine compartment next to a hot manifold.

The Extended Nozzle shooters have the capability to blast fuel from the shooter and have it actually hit the carb booster. When that happens the fuel is immediately mixed with the air rushing past the carb booster in the venturi area. Works well with larger carbs that want the pump shot fuel mixed immediately before entering the intake.

So again, you do not need to rap the throttle 50 times to verify the shooter is working.

You do need to check the accelerator pump adjustment every time you change the idle blade position on the carb (as mentioned by ta man).
Primary or Secondary positions.

I will discuss Accelerator Pump Volume and vehicle applications (swapping 50cc pump and 30cc pump on the carb) tomorrow but will mention that when the pump moves, and the fuel shoots from the shooter, a 30 cc pump is based on 10 shooter strokes of the pump in a collection vial. So each "stroke" of a 30cc pump is 3 cc and each stroke of a 50cc pump is 5 cc of gasoline. Mr "Rap the throttle 50 times" just put 75cc or more of fuel thru the engine that was not needed and just wasted it for the Video Show.

Tom V.