Dream on - 25 cc vs 40 cc.
the reason the 160 engines do as well as they do is that they are burning alky and nitro .
but given that, put a 20x10 MenzS onyour 160 -
this is a good check for torque comparison. can you turn it 6500?
Obviously, the 160 will be way off it's power curve-
different ballgame.
Oh yes -160's turn faster than 40's
but on much less prop load.