The stock internals are designed to handle in excess of 300 HP.

If you go to any MP3 forums there are several MP3s that were n/a and now turbo and produce over 200 hp to the wheels, with no ill effects.

This amount of power is with only 7 psi.

There was a good article in a magazine about the P5s racing in SCCA and how excellant the engine was for producing power. The fact that the factory builds the engines with such close internal specs and excellant balance makes for a real performer