I run a 96 Storm 800 motor in a custom Chassis with PSI pipes, and V-force reeds, and bored carbs. I run about the elevation you are wanting to be in, with that said, we are at 320's for jets. It is going to be hard for people to suggest jets for you because almost no one runs these sleds in stock configuration. If I had to guess though, I would say around 280 or 290's Strictly a guess, you will be able to tell by how it runs and by looking at the plugs. Chances are, it is probably jetted correctly unless you got from another area. You may just want to try resetting the slide needles, and fine tuning your carbs once you get on the mountain. These sleds are heavy, so anything you can do to lighten them up, they will respond well to. I may be parting mine out in the next month or so, If I do it will be after the Ogden races on the 29 of Jan. I love my storm, it has done a really good job for me, but I bought a turbo sled this year, and sadly it is worth more in parts than as a whole. I will let you know if and when I decide to part it. It has all of the light weight parts and long track as well, just remember on these storms, loss of weight equals horsepower. Good luck with it.