That makes me laugh when people talking about 400hp - 450hp on the cummings, they are the same torque number, the 450 is a little faster out of the hole, or maybe will keep a higher torque in hotter weather due to the bigger intercooler, and some L9 are 380hp with 1250 torque,
and if you want a 400hp to out run the 450 light to light, just upgrade the exhaust manifold,
The sport coaches have real torque numbers
a Real 450 hp is the Mercedes by Detroit that little 450hp in the Freightliner 1550 torque, but it comes at a cost,
At the end of the day, what are you towing, the L9 fuel mileage compared to the Mercedes 13liter i bet the 13L get thirsty,
The Cummins 6.7 in some of the new super C's are getting 10 miles to the gallon,
My Ford with a 21,000K trailer is getting around 4 miles to the gallon at the same weight,
I think my back and bladder can only go around 50-60 gallons before i have to stop,