If you are running 1000'-1700' speed runs as you mentioned, I would put in 22x37 gears or maybe even one size up from that. Run stock secondary spring, 54A gram weights, and an HPE Orange or orange and white pimary spring, whichever is the stiffer of the two; can't remember which.
This is all assuming it is with a stock motor though, if you have pipes this setup won't work. I had this setup for 1000' speed runs on ice and ran just over 100mph consistanty. The only cometition was a guy with a '96 ZRT and we would trade wins. With a 1700' run you would almost be running out of gear and should be in the hundred and teens for speed.
This is also a great setup for aggressive trail riding and has an awesome midrange pull over stock.
Also, whe you go to the speed runs, put in 330 or 320 mains. That will make a BIG difference believe it or not! Also put in a worn out set of carbides, or just use a worn set or wear rods with no carbides. Put in an old worn out hyfax and put antifreeze on it just before you make the run. Covering up some of the vents in the hood with racing tape will help, and sit on the sled like you would whe you are trail riding and just lean forward. Don't be like the yahoos out there that try and do wheelies by standing on the back of the track and jumping up and down. haha Just sit normal with your feet in the holder and lean down just under the windshield.
All these little things at up fast at the end of the track!
A forum community dedicated to snowmobile owners and enthusiasts. Come join the discussion about performance, troubleshooting, trails, maintenance, riding tips, modifications, classifieds, accessories, and more!