||"pure" power number that's higher due to the lack of losses in the driveline, engineers have a more controlled setup to tune the engine to where it needs to be. No doubt there's a regulatory aspect to it, too, which would get more complicated, especially if they have the engine in multiple applications.
You gotta figure, the factory measures and rates engines at the crank, modded cars are measured at the wheel. If you calculate or guess crank HP based off whp, it's still theoretical.
Of course, whp is also subject to how the dyno is setup, too, but that's a whole other discussion.
REGARDLESS, congrats on the power numbers - very impressive. One of these days, I'll finally get mine to something respectable. Nice job!