[Tyson Schmidt]

Seems like it's always the R/F that locks up on 911's. This is due, I think to two things.

Porsche (and everyone else for that matter.) builds in a lot of front brake bias so that the car will understeer in panic brake-lock situations. A lot of Track guys dial a lot of this out for better car control. The front always gets more brake bias due to the fact that weight is transferred forward during braking, so the front has more load, and is doing more of the work. But, a little more than is needed is given to the fronts to make sure the car won't spin when the brakes are aggressively applied. (Which is what would happen if the rears locked up before the fronts.)

I think the right front locks up before the left since the driver is adding weight to the left side.

Since the 911 is so light in the front, it's important to transfer the weight forward before fully applying the brakes. There's a method for threshhold braking that involves tapping the brakes to transfer weight forward to load the front tires, then applying more pressure to the pedal once the front is loaded.

If you suddenly nail the brakes, you can be giving them 70% of the braking force while they momentarily only have 40% of the cars weight on them. They haven't had time to load up from weight transfer.