I understand I can change the Taper Bore Pulley associated with the supercharger to boost horsepower however there is a 15%, 17% and 19% unit available and I am not sure which one I should choose. My 2005 Cooper S is driven every day on the street. Any recommendations here on type and OEM product best suited for my needs. Also does changing this pulley affect the manufacturers warranty on the vehilce?

 

I would recommend the 15% pulley. It's the one most used and probably the safest.
Yes. Changing the pulley could likely affect the warranty. But don't let that stop you. It really is a great mod for these cars and the likelihood that it will cause you a problem is quite rare.

 

Pulley will more than likely void your warranty. There are MANY threads on this...

As notes the 15% is the safest and gives a nice boost to the car.

 

Thanks for the input. I will look into this to see what I can find out.

 

Note that the OEM is a friction fit pulley, which is replaced with either a taper bore or a 'direct torque' collar which clamps to the SC shaft.

15% is accepted and safe.
Higher numbers get more boost - how well that translates to power depends on your equipment and RPM range.

Warranty all depends on your dealer.

 

I recently put a 15% pulley on my MCSC & it is a DD. I really really like it & think it is the greatest mod for the moolah IMHO. I have 1-1/2 years left on my warranty & I know they can try to be azzes if they wanna but I don't think I would get denied any warranty work unless it's on my supercharger

 

Your convertible has big tatas, or your pulley?? Sorry, your sig did it...

DD = Definite Do??

 

Superchargers are cheap anyway.

 

ta-tas is sooo yesterday can't you see I've moved on to hooters While DD may very well be someones cup size it is my daily driver