my friend told me that ford rates their hp rating at the flywheel not at the engine, is this true? If so does that mean a stock mark VIII dyno's at the rear wheel at 300hp? If so, that means they have like 325-350hp, right?

thanks,
scott

SAE Net HP is always rated at the flywheel with all accessories, emissions and exhaust systems installed and running. And a Mark VIII would be lucky to dump 230HP at the wheels.

Most of your power loss is through the drivetrain; i.e. the transmission and differential, which are aft of the flywheel. Factor in ~25% loss through the drivetrain (with automatic...standard loss is 20% for a manual transmission) and you're looking at 225rwhp from the 300hp you state.