Though it is theoretically possible to screw up the ABS system with over_the_top calipers and pads, I've never heard of anyone with a problem. At worst, I suspect some of us have deviated a bit from the optimum calibration set by the engineer who designed the ABS system.<ul><li><a href="http://www.stoptech.com/whitepapers/abs_bigbrake_122701.htm">ABS and Big Brakes</a></li></ul>

When I was tracking a ton...I got the ABS controller to act real weird like...hard to explain..something to do with the wheel sensors. I could imagine conditions where the ABS system..expecting OEM stuff...gets a bit confused with the aftermarket stuff.

Even though stopping distances would be shorting with ABS active, I normally try to threshold brake on track and stay out of ABS. One 30 min track session could be the equivalent of a lifetime of ABS use for a "normal" driver on the street. I really don't think the ABS system is designed to handle the extreme service it would see on track.

The back end would also fishtail in straight line braking...felt very odd.