Greetings. my next mod to my MINI is a supercharger pulley. i have my mind set on the 17% reduction, but im not quiet sure whether to purchase just the pulley itself, or if its really worth it to go with the package. can a 17% reduction pulley run on the stock belt? if so, i dont see why i need to purchase the package?. it might not seem like such a drastic difference in price, but when calculating shipping to South Africa, the 2nd option (package) is around 80 dollars more expensive on shipping alone. however, i am prepared to pay the extra if its really worth it. so im hoping the pulley guys have some advice on this one. Thanks!

Option 1 : Supercharger Pulley
http://www.ebay.com/itm/230739721146


Option 2 : Supercharger Pulley Pack
http://www.ebay.com/itm/230761838659

 

Once you change your pulley you will need a smaller belt period. If you can buy the belt there in South Africa to save money then thats one option. The tensioner stop in the package is a precaution from damaging parts when the belt breaks.

 

Agreed; you could probably find the correct size belt locally. maybe that will save you money. You definitely will need a new and smaller belt.

At outmotoring.com, they sell Gates serpentine belts for the R53, (which are also available at Carquest and Napa).

Here is their summary of the sizes and part numbers you'll need to consider:
gates: #060547 =1404mm = stock Cooper S belt
gates: #060539 = 1385mm = ok for stock OR w/ 15% pulley
gates: #060535 = 1379mm = best w/ 15% or 17% pulley (and with either the 0% or 2% crank pulley)


Looks like your best bet is the one bolded...

 

Yup...if you are going to go tgrogh the trouble of removing tge old belt to install a pulley, 100% go with a new belt. The 535 length belt above or the metric equivelnt is pretty common, so bet you can find it in an auto store in the local brand......
One thing to consider is do you have the expertise/tools to swap the pulley....just a reminder, a STOCK PULLEY PULLER WILL NOT WORK. It will tear and bend the sc pulley, but not remove it.
So you must either buy a mini specfic puller or cut the stock pulley off with an grinder/cutoff wheel.....something to consider.
A pulley is great, but take into account local temps and fuel quality...
Seems the 17 is most popular in the us in cooler areas....it makes a bit of heat, so imo if you deal with hot temps, like our folks in California or Florida, a 15% might be a slightly better option. But either way, go with the jcw equivelent plugs...ones that are one step cooler than stock s plugs, and it will help you out to prevent ping on hot days...and change them regularly like on a jcw...each service is what is recommended, so 30,000 miles.
Then enjoy!!! A pulley on a mini is great!!

 

and for those stubborn ones where the correct puller still isnt enough try this