The standard cooper s engine is exactly the same engine as the JCW
& a few mods will give you the same or even more power than the JCW
. The supercharger is exactly the same its only the pulley size that is different, a JCW
will have a 11% reduced pulley but you can buy 15% 17% plus a few others to put on a standard supercharger. The later superchargers from I think 2004 had teflon coated rotors which have tighter tolerances so give a bit more boost (I swapped mine from older version to teflon version & gained 4psi boost) keep the injectors off the JCW
engine as they are bigger & it may have a bigger valve head. The air filter should be different too but there are better ones out there than the JCW
, also it should have a slightly bigger intercooler than the standard s. The ECU will also be mapped different. There is probably more but cant think of much more at the moment.
I have a standard s with a few mods...
17% supercharger pulley
Lightened crank pulley
Orranje stealth airbox
Fletcher cat back exhaust
Dyno'd at Lohen 217bhp
Since the dyno I fitted the teflon supercharger which has given me an extra 4psi boost so its probably over 220bhp now. So you can see how relatively easy it is to get up to JCW
power with a standard s engine