O.S. are calling the turbo plugs The best plug for finals .
Features of the Turbo P3 & P4 are an increased power in the low-middle range compared with the standard P3, P4. Also Quicker response to throttle movements & thus shorter time to reach max speed and a more stable idling (you will hear the different engine sound in idling compare to standard P3, P4). The RP6 & RP7 display the same characteristics albeit without the advantage in idling.