Changing displacement is s huge change, is keeping thing else the same is that a fair comparison.
Take gearing eg.. say I build a 400 hp 273 and you build a 400 hp 440 would it be a fair comparison to have both run 2800 stall & 3.23 gears yes with that restriction the 2800 stall & 3.23 gears would be more optimal for the 440 but if both geared and stalled right it should be a close match on the track, wouldn't that be the same for everything else.
My conception of how this all works seem to go against the grain only say 10% seem to be on my page, I am willing to change my mind but I need more than cause we say so, majority rules etc..
If you asked me explain how 408 makes more torque than a 365 I could answer in one sentence, why isn't there a sentence to explain why a 365 can't make as much power as a 408 with same/similar parts funny thing is the answer I mainly get is the torque answer.