OK, folks who've been close to the WRX: I forgot to check this in detroit and none of my pictures are detailed enough.

Will the WRX be getting the single or dual stage brake booster?

I'm guessing dual, but...

I'm reviewing my assesment of the braking system because of all of the recent bitching about the 2 pot brakes.

After rechecking the specs and seeing that the front brakes are 11.4" diameter, not 11.2" like I thought, I'm calculating that the WRX's brakes will have 94.4% of the surface area of the 298mm 4-pot STi kit.

This is getting pretty close. I'm starting to wonder if the four pots are really going to be needed. I think with a good set of degassed pads (mintex, et. al.) the stock brakes should be more than adequate for all but the most rigorous uses.

Factor in, too, that the STi brakes are a massive chunk of unsprung cast iron, and I really start to wonder...

I've currently got the 4-pots on my RS, but I'm not doing big-track stuff anymore. I was planning on transferring the 4-pots to the WRX, but now I'm not so sure it will be worth the trouble, let alone the unsprung weight gain.

Thoughts?

You can't say how much area is covered by the brake pads simply by calculating and comparing the diameter of the rotors. You have to know either the swept area of the brake pads on the rotors or the physical area covered by the brake pads. And it's not just a matter of the size covered, because with a 4 pot versus a 2 pot system you will have more pressure on the brake pads and hence more friction and better stopping power. But to answer your question, I have no idea if the WRX is getting the 1 stage or 2 stage brake booster.

When I looked at the LA auto show it was a dual stage (of course it may change) I believe someone even got a good pic of it in the engine bay that you could tell.

I wasn't talking about area of the rotors in relation to braking force, I was talking about it in terms of fade resistance. Since the surface area and thermal mass are the two biggest contributors to fade and resistance to fade, that's what I'm most concerned about.

True, the 4-pot will apply much more clamping force, without a doubt, I'm just wondering if I need it.

My RS brakes were always ALMOST good enough, but fade prone. When I went to the STi 4-pots they were totally fade proof, but moved the braking bias too far forward and will put a seatbelt bruise on my chest if I mash the brakes at anything above 5mph.

My reasoning is that with the larger rotor SURFACE, the fade properies will be better (although we're putting more energy into the system with a heavier car...), and with the extra ducting, I'm hoping that maybe I'll just get by with better pads.

Looks like the single stage booster will be the hot-brake mod for the serious autocrossers and roadracers.