Duramax is king of the mountain again

4x4ord wrote:
If the 440 hp rating of the Powerstroke is not SAE flywheel hp what else would it be?

since 1972 federal laws have required horsepower claims to be SAE Net horsepower. That is power with ALL factory stuff hooked up and operating, factory fuel delivery etc. and horsepower measured at the flywheel.

The old SAE gross hp was just that gross. Mfg would add headers, remove air cleaners, disconnect alternator, water pump etc.

The other option mfg have is SAE certified where there is more certification and testing required to a very specific standard test method, but IMHO the difference between the certified and SAE net is probably not something most of us would be able to notice.

I believe GM uses the SAE certified hp for the duramax.