Originally Posted by houston

The 5 port design has more power from the port design . The 4 port has great mileage due to its port design and great power due to its crankwork .

The two engines share similar cranks but the plus 4 has the 15009T crank which has timing increases and smoothed fuel exit area .

The plus 4c has a crank that has all the 15009T work plus a larger opening in the throat of the crank , it went from 9.5mm to 10mm and is smoothed out . Plus4C crank is part#15007T


If you want a really badass 5port get a p5x/xs/xl/xlt. They are all the same and put a 15007T crankshaft in the engine , trust me you will not be disappointed at all