Re: 2015 Corvette Z06: Only a 1.7 liter TVS Supercharger!
Why I am more concerned with torque curves. HP ratings are magical numbers wielded mainly by marketeers.
You have SAE Gross, Net, KW, CV (steam horses), DIN and a slew of others.
I have seen the exact same engine billed with three different HP ranging from 345 to 370 depending on the car line, 500+ hp engines billed at "430hp" next to a street engine billed at 435. Z-28s (original) pull 440 on a dyno but marketed at 290 because the SS-350 was 295.
Also have seen the reverse (suspect the operator had his thumb on the scale when a 390 F*rd hit 300hp).
So HP ratings are for the sans coulottes and to aid salesmen. Torque is what makes you go fast.