Set up the primary bbl for economy and secondary bbl for power........
This type of carb tuning is possible.... but if you go too lean on the fuel, the engine may not feel responsive while running with just the primaries. You can go bigger on the jetting with the secondaries, but again... too much fuel without added air and you will most likely just burn more fuel and not gain any added power.
Ideally you want to have enough air to burn all the fuel in order to reach AFR and stoichiometric mixture.
Without a wide band O2 sensor or some kind data logger to record the AF during testing... from low RPM driving to WOT, you may be guessing, or going by your butt dyno - which may provide some interesting feedback.
Remember you are at elevation above sea level, so your air has less oxygen. Power loss in your engine will be between 3 and 4 HP for every 1,000 feet above sea level. If you are running around 4,000 feet above sea level, your engine will see about 12 to 16 HP loss.
Does this carb have vacuum operated secondaries or total manual with throttle linkage control?
How can you get an accurate MPG reading with only 45 miles of driving?
That's just my opinion - it may be worthless.
Gnarls.
