So I found some silver spark plugs online. does anyone have any comments on silver vs iridium? also there were many different sizes such as.. (19mm reach 16mm hex, 19mm reach 17.5mm hex, 25mm reach 16mm hex, and so on..) i have no idea what these mean and i need to know which one to buy lol. i am also buying nology hotwires to go with them. I have a 2002 mini cooper S. any advice is appreciated!

Do yourself a favor and stick with NGK. Do you have an underdrive pulley? IF so use the NGK 4285 as they are the same as the JCW and are 1 step colder.

why would it be a mistake to go with iridium or silver? or are NGK iridium? because iv been led to believe iridium produces a much more powerful spark than others

The NGK is iridium. Silver is great. Many have had issues with almost all plugs except the NGK's.

Silver plugs wear VERY FAST.....about as fast as the old copper ones that folks once changed every 15,000 miles (or less). Years ago when points were used, and voltages/amps were lower, good conductivity was important to getting a good spark....
But with modern coils, and VERY SHORT wire runs in a mini (remember the old cars with 6 foot cables!!), the need to get the most bang out of the plug due to low volts/amps is gone....platinum and irridium plugs, with service lives of 3-5 times longer only make sense....and you still get a better spark than with the old system.
Also a reality check....
Wrong plug can physically destroy a motor....

should i still use the nology hotwires with the NGK plugs? from what iv learned nology seems to be good quality.

Save your money and buy the NGK wires or OEM wires as they work fine. There are no benefits on a MINI to using aftermarket wires or coils.

Use the money saved for other mods, like a pulley if you don't have one.

the first thing i wanted to do was buy a 15% reduced pulley but seeing as how iv got 116k i was worried itd put to much strain on the Supercharger. you think itd be ok or should i rebuild it first?

If it is not making any noises and you are not having problems, you will have no worries. Many did it with high mileage and have had zero issues.

Honestly, you are wasting your money. You aren't going to gain a thing from those wires and plugs. What they others have said is correct, stick with NGK Iridium and you will avoid problems. We have seen many plugs blow from other brands and it simply isn't worth the hassle.

As for the wires, they are good, but way to expensive for a road car. If you are wanting to get some bling under the hood, look at the Kingsborne wires. I have been running these for a few years now and really like them and the price is right

http://www.outmotoring.com/mini-coop...firebraid.html

I would recommend pulling the SC out and changing the oil in it. At that age it should be time.

There is little (a fraction of one HP by most accounts) gained from one new plug and wires to another new pair....old, worn to new is more...but products sold are mostly the same...some just do more marketing...or have "features" added to look cool... That may actually HURT PERFORMANCE.
My suggestion....
DO NOT BUY PLUGS FROM A SOURCE THAT MAKES YOU pick the needed plug...
Data bases are so common, and use a s plug in a non-s, and engine destruction is possible due to using the wrong plug length....
Buy the plugs from a vendor who knows mini's....
Trying to save a few cents can become VERY $$$$ if you need a new motor.....

One tip...
Drive your car...
Enjoy it...
Don't obsess over what might happen....
Do BASIC mataince and preventative MX....
But if you are paying somebody to do some items....
Like a sc re-lube, then the $800 spent is a dubious expense...
IMO if you are paying a shop $100+ per hour for a full day job, then just install a new/rebuilt one, and be done with it.....or just run it till it fails...do the same...
They a SC FAILS due to wear....seals wear and leak...refilling does lengthen the time till it stops...but does not address the issues.... Kinda like changing the oil in you motor does not help you with the fact the piston rings are worn or you leak a ton of oil....
Many issues on these boards are from well meaning folks that get too involved in stuff they are not fully compantent in and don't understand....many good cars have been messed up, blown up, and much $$ wasted by folks who THOUGHT they were doing right....
Put your plugs in...with a tourqe wrench (failure to use one in a mini can result in a blown plug...resulting in a $300-3000 bill.....).....
Another question....this thread is in the non-s forum...
So just a reminder....
The S has the supercharger...
The non S Does NOT.

As Zippy said torque your plugs. The setting is 22ftlbs. Torque them on a cold engine and then drive it and recheck them again when the engine is cold.

i was planning to rebuild the supercharger myself( if needed). im going to school for automotive so any parts i buy i will install myself.

Save your money. Nology wires are way over prices for no HP gian like they claim. Same with the plugs.
We have some great affordable plugs wires:
http://www.waymotorworks.com/kingsbo...nce-wires.html

and for plugs these will be the most reliable you can get:
http://www.waymotorworks.com/john-co...gs-by-ngk.html

Unless you already know the spark plug number/info you are searching for, buying plugs from Ebay under a search can be risky. Often times I see plugs erroneously listed there for a MINI model/year which I know to be incorrect.....