the motors are the same....the CPU's which control them are not....which is why you are supposed to run HI OCTANE gas in the MP3, and why its advertised as having 10 more Horse Power..
the front suspensions are different ONLY in the respect that the MP3 has a different strut and springs which are a tad stiffer...and lower the car about 3/4 of an inch.....but the parts are interchangable...as in you can put the MP3 parts in the P-5