3 speed autos are the worst , they slip and slipping eats energy in the form of heat.
4 speed auto is vastly better (plusTCC) and 5-sp manual is tops.
Autos can come close to manuals at cruise only, (note Lexus 8 speed)
Lexus, GM and BMS7 all have 8 speeds, to recover this vast waste in a autos.
MPG-not
note, you cant even do the cut fuel coast trick to save gas going down hill.
dont let RPM bother you, each engine has its best economy points.
on this car 40-50 mph is the best economy range, (you can buy a guage that measures fuel , by distance).
monitors Injector Pulse width and VSS speed sensor and does the calc.
on 96+ cars you can get a SCANGUAGE-II for OBD2 port and just press the MPG button and watch LIVE.
any faster , MPG drops, but , on a side kick it drops slower, due to its lower weight and effecient engine.
the relationship of bore and stroke determine performace, google, "under square and over square engines."
then you will under stand. (John Deer or
Hayabusa.org) vastly different, see.