I am trying to get more power out of my Mini Cooper S and I've found some information about the JW mini but i cant seem to find what the main differences are between the 2 engine wise. Can any one Help!!!!!!!

 

If you are referring to the JCW motor, the differences between it's engine and an 04 are as follows:

Slightly modified head
Bigger injectors
Different air intake
Internals of supercharger coated and smaller pulley attached
Higher flow stainless steel exhaust w/ different tips
Different ECU programming.

I believe that covers it

 

great thanks.
The PSI on the supercharger is also raised to 14 compared to 10 on the MINI S

 

Thats due to the reduced pulley size on the JCW cars. The superchargers themselves do not create different PSIs... You can put a reduced pulley on a non-JCW car and have more PSI as well... The superchargers themselves are nearly identical, the only difference being a coated inside of the JCW supercharger, that the 04 MCS did not have... The 05-06 Superchargers had the coating from the factory...