Just like in the subject, I have the hole rearend and suspension is out of the car. I have new LCA's, panhard, and shocks. Will a fater sway bar help with luanch at the track, and how does it help?

 

A larger rear swaybar for launching will help keep the car straight. It really won't help with traction at all.

 

So it'll help keep me out of the wall when I pull the front tires off the start.

 

When you launch, the diff wants to rotate as the pinion trys to climb up the ring gear. That's why those one wheel burnouts are always on the passenger side wheel. Everyone trys to compensate for this by installing weight over the right rear wheel like positioning the battery there. This is sprung weight. The diff will still compresses the springs as it lifts. You can also use air bags to stiffen up that side to keep the diff from trying to rise. This makes it harder for the diff to compress the spring.

The sway bar is the best way to limit diff rotation. It limits the upward travel of the diff since it is unsprung weight. The upward forces are held back by the downward force on the other side of the diff. It won't eliminate the problem but it will add stiffness so that the right side won't lift up as much.