Studs

120 down the middle will work good.Thats what I did on my MXZ700.

I ended up putting 144 on my son's '00 MXZ500 just for extra traction in icy conditions. Normally, 96 would probably be OK for this level of power, but at 100 lb. soaking wet, I figured I'd go to the next expandable pattern level which is 144 (2 in the middle and alternating every other outside). At the same time, I installed 6 inches of Woody's carbides up front because the stock Ski Doo carbides weren't long enough to provide adequate turning with 144 studs. Remember that you may need extra carbide length on the ski's when you stud it. Also, the suspension should be dialed for more ski pressure as the more traction you have on the track, the more it will want to cause your sled to understeer (go straight when you want it to turn).