lobuxracer

iTrader: (2)

Absolutely not. Locked wheels result in much longer stopping distances and loss of directional control. Braking for maximum performance means finding impending lock and staying just on the rotation side of impending lock. ABS now does this for us, but a skilled driver can out-perform ABS and stop in a shorter distance without invoking ABS because ABS oscillates between lock and unlock to achieve results. Every fraction of a second in lock extends stopping distances. ABS is a god send for unskilled drivers, and an annoyance to those who understand how to use brakes properly.

What we are saying about stopping power is, any pad capable of locking the wheel has the ability to stop as quickly as any other pad capable of locking the wheel since locking is NOT what we want to do, but having that ability means it is possible to go beyond the power necessary for minimum stopping distance.

konichiwa3

Here is my train of thought and I would be happy to receive any correction from you or anyone else; the same principles that apply to accelerating a car apply to decelerating hence stopping power.

When it comes to accelerating or braking, traction is one of the major things you have to contend with. Slip ratio of 1 or -1 and you are spinning or locking a wheel vis-a-vis acceleration or deceleration. From a performance stand point of view you want to stay away from either one of these points of slip ratio. There is a threshold area where the best acceleration and deceleration is achieved.

If one is accelerating from 0-60mph, the engine that transmits the most torque with minimal tire slip will cover the greater distance. How quickly a car launches is ultimately limited by traction i.e tires coefficient of friction. However, it would be wrong to state that as long as an engine has enough torque to spin the tire it will cover the same distance from 0-60 regardless of how much torque the engine can produce. This to me is the same line of argument when one states that "as long as the brakes can lock the wheels, stopping distance remains unaffected given a particular coefficient of friction between tire and road."


Going back to braking, where does the torque come from? Braking torque will be produced between the pad and rotors. A higher friction street/track pad will produce more torque on the rotor, more work is produced therefore more kinetic energy is turned to heat energy in a shorter period of time. The higher friction pads are able to do more work in the least amount of time for any given amount of pressure at the brake pedal.

Better feel from a high friction brake pad as you rightfully stated I believe would further shorten stopping distance. Better feel translates to better feedback from the braking system which allows you to modulate the brake pressure more efficiently.

With less than ideal feel one is either under-braking or over-braking which negatively affects stopping distance.

Along with the fact it takes more brake pedal pressure to produce a given amount of torque with a lower friction pad. Every tenth of a second from 60 - 0mph could mean up to an extra 8.8 feet. Yes, every 1/10th of a second!


As for heat which results in brake fade that is primarily a function of the rotors which act as the heat sink.

The calipers will lend to Brake torque. Higher friction brake pads and more massive calipers are part of the brake torque equation. This is all about braking efficiency. The more efficiently you can turn the kinetic energy to heat energy, the better the stopping power.

Brake fade due to heat and the tire model used for calculating stopping distance are very commonly discussed but braking efficiency is rarely mentioned despite how intuitively it makes plenty sense.


Am happy for anyone to poke holes in my presented argument.

randbrus

Has anyone used Power Stop Z23-1440 Z23 Evolution Sport Brake Pads? If so how would you compare them with OEM? Lower dust and noise?

SWeatherly

Yes, I have used those pads and there is a huge significant difference in brake dust. As a test I used OEM on the front and the PS Z23 on the rear. I could go almost a week without significant brake dust on the rear, where the previous OEM, it was maybe the same amount in 2 days or so. I've had them now for about 6 months without issue and they keep the rotors always polished looking.. just a good as the OEM. Hope this helps

TOPHER9425

I infacrt just upgraded my Stock Rotors and pads at 61k miles......alot of highway driving, hence my longevity of the stock set up. I went with 2-piece RR Racing rotors front & rear and paired them with power stop evolution pads. Total cost was $2300 + install. Love the look of the rotors and the dust is almost non existent.