I own a z 440 snow pro fan. Raced it this weekend and lost in the 500 Improved class in the finals. Walked him out of the hole bye three sleds, he just past me at the finish line 660 ft. (got second)
Ièm thinking of changing the gearing can someone help.
If you gear up you'll probably get smoked the whole race instead of at the finish. 660' is all hook up and acceleration not top speed. Play with your clutching to get the best acceleration and shift to the proper RPM at the finish.
I don't know what the max RPM is for your sled off hand but, that sounds a little low. If you know that would help. I know my 600 stock was supposed to run 8500.
If you're not running close to max RPM at the finish line you are not taking advantage of all the HP your sled could make. That tells me you either should gear down or clutch it. You're probably geared low to begin with so work on the clutching.
If you know what you're running now that would help.
I do believe that is low. In general higher displacement = lower max rpms for peak HP (the zr900 for example keeps max rpms around 7200-7500). I believe the 440 liquid racers run around 8800-8900. Check what your max rpms should be and check what you're getting to, then you'll know to clutch/gear accordingly.
This is a Z-FAN. That is about the right RPM's for that machine. They come from the factory running 7600. I would definately try to run higher gearing. Whatever you have in it now, try either 1 tooth up on top or drop 1-2 on the bottom.