I have only a high school level understanding of physics. I was on 1010tires.com using their calculator and it thew a warning about using larger tires might lead to brake failure. Caliper squeeze the disk, force of the road acts against tire in the form of torque, r x f due to static friction. The greater the radius of the tire the greater the torque. Also increasing the width of the tire will increase the surface area under static friction. I'm running 285/30/20 in the rear, I know it looks a little like a toy Hot Wheels car. The car stops fine, but should I consider changing the brakes for safety or are they over engineered ready to accommodate heavier vehicles such as the LS?

I see a lot of people changing caliper but do they change the disc to a larger one or just slotted and drilled with the same size , for better heat dispersal?

One solution is crappy tires with poor friction.

For those running with 285/30/20 what has been your experience with how long your brakes last.

 

2gs forum has some great discussion of that issue.
Stock brake should do fine if your tires are good.
However, the brake fading will be more of the problem if you like doing some spiritual driving on 20"+.
BBK could be one of the solutions.