I've got a 2003 MCS with all of the JCW goodies on it (head, exhaust, JCW tune, JCW pulley...what ever the 03' JCW kit consisted of). I was told that it's the 200hp JCW kit ....because the 210 kits (with 380 injectors) didn't come out until 05.

I'm currently getting right at 13psi of boost at WOT. I've been toying around with swapping the JCW pulley (11%?) for either a 15% or 17% pulley.

What kind of HP improvements would I see by swamping pulleys? What "%" is the JCW pulley? I've seen people calling it everything from 11% to 14%.

It it worth the trouble swamping out the JCW pulley?

Thanks for the info guys!

 

First the JCW pulleys are notorious for being major PITA's to get off, a nunber of them have had to be cut off, and once you start, there's no going back.

As far as net gain in boost I don't remember what the exact #'s are I think a 15% =14.75 & 17%=15.25 but again I'm not sure, but if you do decide to do it, go 17%, the gain from a 15% will def. not be worth the effort if removing the old pulley.

 

Thanks for the info guys!

 

worked great for me, yea cutting the pulley off is the best bet(for most R53 too) I had JCW 380's and the upgraded MINI tune to go with them.

 

The least amount of extra wear on your supercharger would be to use a 15%, since it is an early JCW it does not have the CAI or the 380 injectors. The addition of either or both with the 15% will be noticeable.

 

I don't think you will notice much...
The jcw pully seems to be well sized...
The 15 or 17% will do more to shift the boost to lower rpms, giving you more low end grunt, more streetability, but at the cost of less top end due to heat..like all things it is a compermise.
Biggest issue with removing a jcw pullie is finding the right puller....
They are around, but kinda rare...
Now if you do a pulley, injectors, and a tune...you will be wowed!!
the head on the JCW is mildly ported, but i think you would notice quite a gain...
Since the 380's are maxed out with a JCW (pretty close to it at 210hp), bigger injectors would be good imo. Ask your tuner if you go this route.

 

you will notice much and just cut it off, you won't ever put the old one back and its much easier