special track tyres

want some special tracks on me fender, found they did well on the disco, apart from thinking i was being followed everywhere by the police helicopter
but am baffled by sizes. was looking at 285/75/16s but ive just been pointed to the new size of 33x12.50x15 whats the differences?? and what size rims would i need?? ive got standard wellers at the minute but was looking at new black modulars

15 inch tyres generally require 15 inch rims.

10x15 rims

which would be the bigger tyre??

285/75/16s

Tyre Size Calculator @ ExplorOz Articles

But remember bigger isn't always better.

I quite fancy getting some 15 tyres..

I currently have 265/75 16 Special tracks and the tyres are brilliant in the sticky stuff... but I really like the look of 15's....

keep looking on ebay for second hand sets of wheels and tyres, but cant find anything decent