[Barry_R]

You cannot just pull a jet number out of the air. Depending upon the emulsion and air bleeds in the fuel package you can have the "right" mixture with jets that are 10 numbers apart in different carbs.

I have run a lot of Quick Fuel carbs on the dyno mostly right out of the box to start. Once you get a handle on wide open throttle mixture (often a couple jets leaner based on experience) you can start tuning on the power valve channel restriction versus primary main jet relationship. Leaner main jetting can sharpen throttle response and improve cruise mileage when coupled with larger power valve channel restrictions to maintain wide open throttle mixure.