I bought the optional Losi springs for my slash. I am running 4.1 on the front and 3.7 on the rear. I have 40 wt shock oil in the front and 35 in the rear. My problem is I am still bottoming out on the jumps including the single. I am thinking of running lighter springs and 1 hole pistons in the rear and maybe the front. My other problem is my track is farely smooth with the majority of the bumps being pot holes in the corners. I noticed it seemed to bounce a little over the potholes. On the straights the bumps are real small and I can hardly tell the truck is bouncing. I am thinking I should not worry much about the smaller bumps. My slash is handling really well with this set up however. I am wondering if I am over thinking this.