I recently picked up a 2005 Polaris Predator for a good deal due to the fact that the carburetor and air box was having issues. The air box on these things are a very poor design and fall apart. Instead of buying a new factory style replacement I installed a rubber hose and mounted a uni filter under the front plastics. I searched all over the web on what jets and sizes to use to compensate for more air but not a whole lot is said about jet sizes. My machine has a Sun World carb and came with a 82.5 main jet, come to find out it uses Mikuni VM 11/22 main jets, I ordered 95, 105, and 115 mains. The 115 runs much better but still needs more fuel so I will be ordering larger sizes to try. It was also a pain to start and didnt idle very well which I read was a common problem on these machines. My predator came with a 25 pilot jet which happens to be a Mikuni VM 22/210 jet so I tried a 30 but could go a size or two bigger on that one too. Im at 5500 feet elevation and my machine is stock other than the intake and CDI jumper wire removed. I also plan on removing the oil injection soon, if anyone has any input or opinions i would like to hear from you, thanks!