Alright Dean...
I'm a little confused by this "trap" I fell into. I understand what you're saying about the brake's transition from dynamic to static friction being able to lock tires that would otherwise still have rolling friction to spare. But if you read my post again:
Quote:
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Originally Posted by me
Now, if I were able to lock all 4 tires at the same time (or the fronts just slightly before the rears) during straight line braking from high speed, then I'd say that I'm "at the braking limits of the tires". At that point, my bias is just right, so I am using all my available traction to slow the car. And if the pedal feel is such that I'm comfortable and modulation is predictable allowing me to brake just above the locking threshold, and if the brakes don't fade, then I'd say that my brakes couldn't be improved.
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I mentioned being able to modulate the brakes to stay above locking up the tires. Perhaps I wasn't explict enough, but it was my intention to describe the situation you later fleshed out: brakes that decelerate the car at the maximum
dynamic friction of the tires. At that point, your brakes cannot be better... they are not the bottleneck in your braking performance.
Let's look again at your "binary brake" system. That extreme example actually demonstrates that *any* brake that can lock the rotor can be used to brake "at the limits of the tire" provided that they can be modulated fast and accurately enough. As you stated, you can theoretically lock the rotor and unlock it w/o the tire itself ever locking up as long as you unlock the rotor before the tire's sidewalls run out of flex. Using this knowledge I could actually design a computer controlled brake that would lock and unlock thousands of times a second to bring the tire to its limit, and threshold brake without ever locking up a tire. (Although you'd heat the bejesus out of the tires... in fact the brake rotor wouldn't heat up at all... those tires would have to generate all the heat that results from stopping the car!! )
The same goes with regular brakes. Lets say I've got a crappy pad that has a very quick and harsh transition from dynamic to static friction. i.e. the pad would cause the tires to lock at a deceleration rate less than the tires "maximum" rolling friction. You would argue that a "better" pad with a less harsh transition would prevent this from happening, and thus would improve the overall brake system. While I won't disagree, I want to point out that a better driver, or a super-fucking-good ABS is also a solution. If I were to be able to modulate those crappy pads, they'd also allow tire-threshold braking, just as in our example binary brakes.
What's my point? Well, I'm not sure.
Given the choice of harsh transition or smooth transition pads, I'd clearly go with the smooth pads since they make driving at the limit easier, however I'm not exactly sure how to find out which pads those are... it's not like that's labeled on the box. Frankly, I just want brakes that stop well, resist fade, and don't feel like I'm stepping on a wet sponge.