2014 Ultimate 1 Ton Challenge results

If they had raced a 3.73 Ram against a 4.10 Ram, the 4.10 would not necessarily do any better in any one particular test but could possibly have done better or worse in some of the hill climbs. Look at it this way: the Cummins is capable of delivering a certain maximum amount of horsepower to the rear wheels. Let's say that number is 300 ponies. Now some of that power will be used to overcome rolling resistance and drag so let's guess that at 50 mph there is 220 HP available to pull a loaded trailer up a hill. By definition 220 horsepower is enough power to lift 121000 lbs 1 foot in 1 second. Now consider a particular hill: say one with a 7% grade: at 50 mph the truck and trailer are gaining elevation at the rate of 5 ft per second. If my assumptions of available rear wheel power are right the Cummins could pull a 24,200 lb truck and trailer combination up a 7% grade at 50 mph (121,000 lbs divded by 5 equals 24,200 lbs). In order to achieve that maximum speed of 50 mph the transmission and rear end need to have a ratio that will allow the engine to run at the rpm it makes maximum power while spinning the rear 50 mph. If the rear end is geared too low the truck will upshift and the rpm will drop to where the engine makes fewer ponies and the truck will slow down. Now choose a different hill or different weight and the perfect gear ratio is something different. This why the Ford was able to leave the Ram and Chevy in the dust on the Davis hill but was very close on the Eisenhower. It got stuck between gears where it couldn't make its 440 HP.