i used to get in top gear as soon as possible with very light throttle loads , however im told thats wrong.
the advice was accelerate briskly [about 80% power] fully utilizing the peak torque segments of YOUR engines power curve in all gears then at cruise around about peak torque for your engine .i go into top gear [4] at about 40MPH and thats some pretty fast stick whipping at 80% for sure
not to say you should red line the thing in the low gears. but run it up until you can fall into the next gear at a good torque #
a power curve chart [fuel-power] is helpful in deciding the best engine speed shift points
notice on the attached chart for my engine that the lowest fuel consumption mirrors the highest torque..
based on this chart i up shift about 3200- 3500 RPM , never run below 2000 RPM and cruise in the big cog at 2800-4500 RPMs. thats between 50 & 80 in top gear
all engines are different.. with *experience* you will develop a feel for it based on subtle sounds and vibrations ..well at least with the machines i run you can ,vibrations and even the sound the carb makes as the throttle plate opens
i do use a manifold vacuum gauge , which is helpful in judging ,i accelerate at 5-10 INHG and like to pull hills at 10. cruise at 15-18 INHG.
all engines are different and have different power-fuel charts. i think they should put them in the operators manual.
maybe this makes sense to you maybe not , maybe its the *right* way maybe not.
just my thoughts based on a lot of miles in many different types of equipment
