Quote Originally Posted by Evan78 View Post
Did you have your ABS controller replaced under the technical service bulletin (TSB) for 2002 and 2003 WRX's? This was a common complaint that Subaru attempted to address, although I don't know how much difference it made since I never had the service performed on my car. I put 130k on my 02 WRX and I experienced this issue several times.
Yes, I had that done way back when. The difference was noticable but not significant.

With due respect to the OP, who tried to refocus this thread to his original question, I'd like to add something to the other things that have been said. Rather than dwell on my experience as a controls technician I think I'll just say a couple outrageous things which should connect a few neurons. I think the turboys will love this. Here goes.

1) Mass and mass distribution of a car have no effect on the performance of an ABS system because, ultimately, it is all controlled by a smart box. In other words, you can put the WRX ABS in an 818.

2) Flow rates and orifice sizes of a turbo system have no effect on the performance of the engine because, ultimately, it is all controlled by a smart box. In other words, you can use the factory TD04 wastegate on an aftermarket GT3076 turbo.

Alright, I might not have phrased my comparison perfectly, but I hope I've made my point. If anyone wishes, I can ramble on about mechanical systems, controls, loops, and the mysterious box, but I really hope that's not needed.