Both engines tune and run very well. The P5 has a nicer port timing profile on the sleeve but smaller exhaust surface area so it tends to make more torque but the Plus 4 will out perform the P5 on top. The Plus 4 has better crank timing profiles than the P5 which will also make it perform better up top. Both engines work well in a truggy with the proper setup. However, a nicely modified P5 will put perform the Plus 4 in every department including run time and will last as long or longer than the Plus 4. My race ported P5 costs about the same money as a stock Plus 4 and will have more power all around, will be very easy to tune, will get 10-12 minutes of runtime in a truggy and will last 12 gallons if treated properly. My race ported Plus 4 runs side by side with the P5. I have both engines in stock in either stock or modified trim so if you are interested, shoot me a pm.