The only variables between two motors and their HP and TQ DYNO charts and output realistically are just TQ and how high they can rev.
The TQ chart will determine what the HP chart will look like, so if two motors are made similar enough to produce similar TQ curve, no matter what it is, turbo, NA, I4, V8… their HP charts will be identical.
With that said, how the NA engine is designed, whether it’s a V8 or a turbo 4 will dictate what the TQ curve looks like accordingly.
*submit graphs.
Also high revving is a huge benefit of smaller motors, since with the same TQ output, if you double the REV’s you will double the HP figure.
Mostly the last part. Doubling the rpm the vehicle can rev to will not double the power. Look at x car’s dyno and see if the hp is 1/2 peak power when the rpms are 1/2 of peak power rpms.