Ideally you have a turbocharger in those ideal super efficient high MPG low rpm schemes.

It takes a vacuum gauge to get the throttle position just right to pull off the low rpm thing too.

want better mpg? do something about the frontal cross section of the car, a front spoiler helps at highway speeds.

the band of efficiency on the 60 series 5th gear with the 3.7 diff starts at 75mph, driving 60mph in 5th is not a fun thing at all. yes an A15 will get a car going well over 95 mph pretty easily.

wow, so far off topic ;)