'68 440 auto carbs

[histoy]

Could someone explain the difference between the Carter AVS 4429S (used with auto trans and no AC) and the Carter AVS 4637S (used with auto trans with AC).

[tan top]

my memory is not what it was but i think it is some thing to do with   the idle speed/ mixture  when the car is idling in drive with the A/C on , or  comming off idle  under the same conditions , richening the mixture at that moment or something , but not altering the basic idle/ mixture settings,   might be wrong on this though i'm trying to think back  15 - 20 years ago  when i wondered the same thing    

[Shakey]

I went through this while looking for an AVS for my '69 440 Auto no AC Charger.

I was told something similar to what tan top had said but I recall being told about the "jetting".

I was told that an AVS from a car that had AC will work fine on a car that doesn't run AC.  You will sacrafice some fuel mileage but gain a few hp.