Then spin the 632 to 15k, now who's winning again? This is why this argument is circular. The 'common wisdom' is correct - bigger wins every time, but you keep throwing imaginary crutches at the 'bigger' motor. Apples to apples, displacement wins. HP is just torque times rpm, and torque is just force at a distance. Increase the force (bore), the distance (throw) and you increase torque. Displacement ups both of those. Whether an engine can continue to make HP above the torque peak all depends on the heads and the valvetrain. Using 'similar' build arguments is meaningless with such a rhetorical question.