First post, just got a 13' Si in February and it's time for me to stop lurking the forums. I have an issue with braking that is only noticeable above 100 mph. 90-95 doesn't cause the issue, just anything over 100. Basically what happens is that the car shakes (one time very violently (was from 133ish), and left me with a stuck caliper on the front right passenger side for 20 mins) when threshold braking (or basically the amount it takes to slow down sternly at that speed, doesn't have to be right before ABS engagement). The pedal feel when this happens is different, sort of harder to press/ stops earlier without the same feel as normal braking, and when the brake locked up I would push in the pedal and hear a "whoosh" similar to closing a bellows. I honestly feel as though when this happens that ABS would not come on if I pressed farther.. It feels as though I am locked out of the ability to use ABS when braking from 100+. I have never braked at the fullest potential of the brake system in this car, so I doubt that the rotors are warped. I'm clueless as to why it only seems to happen above the round 100 mph mark but that seems to be the ticket for it to occur. My brakes have not locked up since, and I have tested it since the front caliper stuck. The car does not seem have the same sensation braking at high speeds as when I first got it, but never felt as composed braking at high speeds as say, my S2K did, it always has kinda shook and felt something as if it was gliding on air to a stop. That's understandable to an extent, but I have never driven a car with braking characteristics like this one. Any ideas? I did not take it to the dealership after the brakes locked up so I'm kinda down to speculation at this point. Thank you for the input!