Ford 6.7L 1050 ft lbs TQ at 1,600 rpm, 475 HP at 2,800 rpm

4x4ord wrote:
I think you're right that a 515 hp engine in a heavy duty truck cn put out peak power all day long. These pick up truck engines may also be capable of running at peak power all day long. It is possible that the reason they don't make advertised hp on the Ike run is due to the extreme elevation. I wonder if the turbos on the pick up truck engines are capable of pumping enough air at 10,000 feet elevation to allow full fuel to be delivered? Maybe fuel is restricted under those conditions to prevent excessive exhaust gas temperatures?

Big trucks do lose a bit of power at 10,000' elevation. Even if the turbo has excess boost capacity, it'll be running at a higher pressure ratio to attain the same manifold boost. This means high intake air temperature.

The fan (40 - 50hp) would either run more to move air across the intercooler (much harder in thin air), or run the same, but with hotter air (less O2) reaching the cylinders. Both saps power.

I also doubt the PS or any other pickup engine can sustain full power up the IKE.