The X' is slightly heavier than a no frills RR. So, front end rise IS important. The better the weight transfer is, the BETTER the "hook" off-the-line. I'm assuming you have the subframes connected, so the wisest things to do is make sure your SS or Caltrac springs are set with the rearend correctly shimmed for the proper pinion down angle. Front end also has to be set for maximum rise under acceleration, but not uncontrollable. The trick is to shift weight to where it's needed - over the rear wheels, under acceleration. And a pinion snubber can't hurt either, just makes traction even better.