sledneck_67
By tightening the springs you are giving the shock more pre-load for the compression stroke of the shock. this means that the overall ride will be stiffer but it will be able to handle larger bumps without bottoming the suspension or having the nose of the sled dive down as far. Since suspension set-up is more about personal preference and riding style then anything its tough for anyone to say what will work better for you. The stiffer the front shocks became the quicker it will react to your body movement on the sled.
I would find a small area that you ride in and ride around so you can feel how your sled reacts to the terrain. then tighten up the springs a little and ride around the same area again to see if the sled feels any better or reacts better to your body movements. It is a give and take thing. You may find that it works better in one area and worse in the others. I would just play around
