Some BBK's may be significantly lighter than the OEM brakes, thereby reducing unsprung weight and improving handling.

 

that's a biggie

 

yes and no. Its the brakes mass (weight) that allows it to handle repeated heavy uses. So while you might save weight, you can and frequently reduce the performance.

In the s2k the oem brakes perform so well that most after market systems before less well. Again thats not the same on every make, but in the s2k's world many of the lighter than stock kits can reduce the performance.

 

yes, you'd have to decrease weight in the right components

 

This means that if you have two braking systems with the same dimensions, but one is made of lead and the other steel, that the lead one will take the abuse better?

I'm just thinking outloud here, but I would guess that the resiliency of the braking system to heat would determine it's ability to not fade with use. This resiliency could be affected by choice in material, heat management, or both.

 

thats exactlly the point I was getting to. Im sure you took tires into account in the first place, but you shot your example in the foot by mentioned locking up the wheels. The wheels "locking" (which in reality means tires skidding foreward) indicates that the tires are undersuited for the braking force being applied to them.


That being said you have too many factors running around at the same time in your analogies. If you make it simple with 2 cars with identical master cylinders, weight, brake pads, tires, etc.. the one with the bigger brakes should stop quicker due to the extra torque from the longer rotor, etc...although in the real world this simplification isnt necessarily practical or realistic.

 

All this stuff that has been posted here so far is pretty much correct -- approximately. However, there are some non-linearities that have been ignored.

For instance, the CF of the brake pads decreases with rotor speed. It's not just that there is more kinetic energy to absorb from the high speed case, but also the pads actually don't work quite as well. So in order to have the maximum braking capability allowed by the tires at top speed, you need to to have an excess of braking capability at low speed.

There are a number of other things that likewise are not accounted for in the simplified linear explanation, but for the most part, the approximation is good enough to explain most of what is going on.

 

Should we all consider here the type and quality of the tarmac that we drive on?

For example most of our roads here in Greece and specially in Athens where i live, are of the worst kind. I have new oem rotors front, stock pads and Goodyears F1 on a 17inch set. Bigger brakes on a slipery tarmac might also do nothing because abs is kicking in and no positive result in the process.

On the track i have not marked brake fading after 20-30 minutes.

Perhaps its an illusion for me to thunk that if i get a bbk, then the feeling would benefit much and the stoping distance will be reduced..

 

Sounds like that's the case.

 

No because the lead would melt at just about any normal brake temp. But yes the mass of the rotor is what allows it to soak the heat up while being used. The heat managment is how you get the temps down between brake applications.