Check out atvoutfitters.com I got their performance kit for the foreman 500. It was an HMF utility exhaust, K&N filter, Outerwaers Pre-filter, and jet kit. Their jet kits just come with 3 oem jets, which is all you need. Price $299 plus shipping. I think you have to add $20 for the QS1 pipe, it tells you at the bottom of their page.