<VV> Re: main jet vs idle

[BBRT]

In most carburetors, when the idle mixture screw is out of range, meaning 
more than 1-2 turns out from soft bottom ( relax Joe-<ggg>) , it means the 
idle jet is the wrong size. The idle jet in a Rochester 1 bbl is the 
restriction in the idle well tube. There are of course air restrictions via 
the holes in the venturi cluster and in some, a small pressed in 
bullet-shaped brass "jet" with a hole in it-in the idle air vent passage. 
These determine the air/fuel mixture in the idle and transition circuit, 
drawing from the main well. I find it difficult to understand how the main 
jet would affect the idle and the transition or sometimes called the 
progression circuit, during low speed operation.

Chuck S
BBRT