Thanks for the info. I just found this on the Firecat info page.
"Krom" on F7 heavy spring kit (recommended for riders over 225lbs)
Krom on 9/18/2002 5:56:00 PM
Cat reccomends installing the 20%stiffer kit (for riders over 225lb), it comes with rear springs, a center spring, and shock valving updates. The firecats are sensitive to suspension set up, you should consider having the kit installed. it is PN 3639-064, for std suspension sleds, and 3639-065 (pretty sure on those #'s but I'm working from mermory, your dealer should have them though) for sno pro sleds, at $85 its a pretty good deal, as the rear springs alone will run you about 50.
The standard suspension part # is good on Brownsleisureworld, but didn't check out the sno pro p/n.
catfish