Throttle Stopping 2 circuit Carb VS. 3 circuit

[cujo3116]

I know most of the "throttle stop" carb builders seem to be using 3 circuit carbs on their applications and I'm trying to completly understand the advantages to this?

I was told that the intermediate circuit is what is used when a car comes onto the throttle stop. So the tuners are leaning out the intermeditat circuit to help keep the engine from wanting to make power and climb on rpm while on the stop. This makes sense but is it only useful if you have a 565+ cubic inch motor? what if your still living in the 499 or less area like myself and a buddy?

I have been using 2 circuit carbs on both my combos (S/g and S/St cars) and had luck with them. However a friends car has a 3 circuit carb, so I'm trying to determine what effect this style carb may have vs the 2 circuits.

If one was to start changing air bleeds in the intermediate circuit what should they be looking for in regards to a A/F ratio while on the stop using a 3 circuit ?

What have others seen that only use a 2 circuit?

Thanks,

Andrew