I wonder if the graph is for a 4x4? If you run the numbers with a 20-25% added in I come up around 287 not our advertised 310. I was hoping the tuner would get closer to the 50hp but this may be with exhaust, CAI.
I'm not sure what you mean, but I think you may be misreading the information...
The stock (peak) numbers posted by dodge (310 hp and 330 lbft) are at the flywheel, not the rear wheels. The stock (peak) numbers at the rear wheels would be more like (310hp * 0.80) = 248 hp. This is for a guesstimated 20% drive train loss. Just an FYI, drive train loss is not truly a percentage loss, but it is relative for a street car. For example, if you have a 500 peak hp engine in a car, and you get 400 peak hp to the wheels (20% loss), then add nitrous or something and have 1000 peak hp just say, you still only have 100 hp loss to the wheels (not 20%), as the drive train didn't change at all (this is just an example, not reality, as realistically you would have to beef up the drive train to handle the extra power most likely).
So just say stock (peak) numbers are 310 hp at crank, and 250 hp at wheels.
Superchips claims to add 50hp with their 91 tune. Many confuse this and say their claims are bogus, but they are not actually; the 50hp is not a peak gain, but a max gain. It is not 50hp added at the peak number(310 flywheel hp), it is 50hp added at about 4,000 rpm. The max gain on the 91 tune if I remember correctly is about 16hp and 33 lbft.