Holley Jet size

Yes. I'm trying to keep to initial basics and small steps.

I'm assuming its high likelyhood that when the engine is first started, someone may crank the idle speed screw in to keep it running. Figured after its running, kendog can then readjust the primary thottle position to be between .020 and .040"
Agree that will look close to square.
If someone needs a picture, here's the amount a primary throttle slot is visible compared to a drill bit shank.
The big hole above the bit is the idle discharge port.
The small squareish cavity by the end of the bit is the transfer slot.
View attachment 1715334348
Now off the top of my head, I sure don't remember what size that bit is! That's why notes are so important.

Below is the secondary side of the same carb.
A very small drill bit is sticking out of the secondary idle port.
Its very small for two reasons:
The hole itself is the idle port restriction. There's no needle valve (idle mixture screw) on the secondary side.
It's provides only a little fuel, and most consider its main job is as a weep so the secondary fuel doesn't get stale.
Off the top of my head, the holes here are around .020" diameter - I'd have to check my notes... :)
View attachment 1715334351



That .020 sounds close. With what you can buy today for so cheap there's no reason to get a carb with 4 corner idle. Then you can control the secondary idle side better.