Depending on which carburetors you have, you may not be able to adjust high speed mixture. My twin Carter W-1s use mechanical metering rods, the more you step down, the richer the mixture. If yours use power valves, then I don't know what you would do.
I can tell mine is lean when the transmission shifts to the next higher gear, if the throttle is only partial open, it will lay over just after shifting, then pick back up when I shightly let off the throttle or step down more. If I richen the mixture by way of metering rod hight, I can get rid of that lay over, but then it runs richer then I like it to. When they are adjusted a touch rich, under full throttle you can hear it pulling hard and feel it. When lean, you can hear lots of air being pulled in but the seat of the pants feel is just not quite there, its not a smooth steady pull.
My A/F gauge shows just what I can feel, it goes way lean after it shifts, then settles back to normal.
Cruise speed ( 65 mph ) it runs about 15.5 to 16.0 Air to fuel
Idle 750 with a/c on 14.5 to 14.9 depending on the weather or fuel quality
Full throttle 4500 max rpm 12.7 - 13.5 A/F ratio
Ideal ratio is 14.7. My fuel mileage went up drastically when I started leaning it out after installing the A/F gauge and O2s. It ran pretty good but smelled like fuel all the time before.
