OK ,but with EPI'S kit it comes with a new helix and spring. And they DON'T like to give out any info. They make a special kit for "mudder's" with bigger tires. Anything else would just be a guess as to what you'd need. For mine they just have a smaller set-up because my quad is"to small to really get into better kits" according to them. Read that as 'not rich enough to pay for a bigger ,badder kit" because I don't own a newer,more expensive quad.