Rotor Swap
 

I'm looking to get into swapping rotor between rpm and torque. Do you need to readjust the timing of the motor or it is still good to leave it alone? I currently have a rpm in the can but I want to try at torque one out for testing and track setup.

A different rotor completely changes how a motor behaves. So yes the most optimal timing will change.

Unless your aim is more torque at the current timing.