Generally with diesels the torque is about 2x the horsepower. As for gas mileage
these don’t use gas… The fuel mileage greatly depends on the driver, vehicle, and other mod’s. I have a 6.0 and I can get anywhere from 15 to 18.5 mpg with the same tune on the same daily commute depending on how I drive (which is directly proportional to what kind of mood I am in
).