M/T Pro Bracket radial

No sunshine and rainbows. Left everything set how it was with slicks, set the radials at 17.5 and spun on the first pass. Backed my shocks down from 5 to 3, launch rpm from 2500 to 2300, and pressure to 16.25. Hooked but was still .02 slow on the 60' and a 7.80. Brought the launch up to 2400, tried 16.5# hooked for a few feet then spun bad resulting in a 1.80 60' and a slow 7.92. I usually run 7.70.

The car seemed to unload on the last pass. Does that mean I need to soften or tighten the rear shocks? They're the Ranchos that came from Calvert. I have a video I'm going to try to post.