This is information, not advice. You are responsible for your own actions. Furthermore the information may be inaccurate. You are cautioned to independently verify anything you use. Beware of installing high power external devices such as super-chargers and nitrous without strengthening internal components, driveshafts, transmissions and differentials.
Many people focus on the former and neglect or degrade the latter.
The stock third generation RX-7 achieves an astoundingly high level of both. The most radical engine modification is to replace a two rotor engine with a three rotor , which has been done by enthusiasts, or even a four rotor , which is limited to serious racers such as Jim Downing and Mazda . Paul Ko analyses the differences between the 13BT and 13B-REW engine blocks. The main radical modification to the engine for performance is to change the porting of the engine by removing metal at the openings. This allows the engine to breath in more fuel-air mixture and expel more exhaust.