[IsaacCarlson]

I DID NOT READ ALL THE POSTS...just to let you know...

My dad used to have a trucking company and ran 21 gears. He knew the gearing inside and out and did his own work. He could get an empty truck up to speed faster than most cars. He knew exactly what gear he wanted to be in and never missed. I used to ride with him in the mountains and we would see spots where trucks had "run away". We would get passed by drivers who thought they could ride the brakes down a mountain and melted them, and yes it looked cool! He averaged 8-9 mpg if I remember right.

A large engine can get very good mileage if it is tuned to put out loads of torque at low rpm. A semi might only have 500 HP but they can have 2,000 ft lbs of torque!!! Once you run that through a tranny, you have WAY more than enough torque to get a load moving.


The thing with I-6 engines is the overlapping power strokes. You can do more at a lower rpm.