velocityhead

iTrader: (3)

Ah, so the BBK debate returns. Already been half-beat to death...

I'll save Amby the trouble of explaining it again. See here: https://www.evolutionm.net/forums/09...alliart-2.html

If your rotors are glowing red, then perhaps a BBK is worthwhile for you. Otherwise you can get the same braking power with some good rotors and pads.

ambystom01

iTrader: (7)

Bingo, BBKs are for cooling, not stopping distance.

MR.Wicked

yes and larger rotors give you a larger moment. i.e. like a larger lever arm. Why do bigger brakes exsist then hmmmm ? Hydraulic pressure for most braking systems is dependent on the ccs of the piston cavity and the piston dia itself. The two factors that play into braking distance are three items contact patch, pad area and rotor dia. This also has to do with less force needed to exert full braking force, i.e. why new car manufacturers have embraced brake assist. Generally yes BBKs are mainly for better modulation and fade prevention but if your factory brakes are junk like the stock lancer 60-0 in 164ft and the evo x in 117ft and it even weighs more...... I don't we are talking about the same set of circumstances here.

yes agreed but if you have substantial fade you will have longer stopping distances.

ambystom01

iTrader: (7)

Bigger brakes exist because larger rotors have a higher thermal capacity and can cool better, larger calipers means more pistons (which can help with pedal feel among other things) and larger pads means better pad cooling and better longevity.
You're arguing against established brake knowledge and physics. Pad area has no effect on stopping distance, nor does rotor diameter. You are welcome to the research yourself, but suffice to say you are wrong.
Real world showing what I'm saying

http://www.zeckhausen.com/Testing_Brakes.htm
http://www.modified.com/roadtests/07...est/index.html

Good FAQ that discusses the physics behind brakes

http://www.ffcobra.com/FAQ/brakes3.html

Nice quote from that FAQ

velocityhead

iTrader: (3)

Your hydraulic pressure should be the same with a BBK unless you're upgrading other braking components further up the line (like master cylinder).

Bigger pads won't help unless you have more piston pressure to keep the pressure-per-square-unit consistent. If you take a car and throw on some pads that are 2x the area, the pressure between the pads and rotors will be LESS per square-unit than the smaller pads, unless you can increase the fluid pressure in proportion to the increase in pad size.

From a physics "lever" standpoint, you are correct in that rotor diameter plays a part, though the radius of a BBK rotor isn't a huge difference from the stock rotor. Also keep in mind with a larger, heavier rotor, you now have more rotational inertia to try to stop (just like heavier, larger diameter wheels)

ambystom01

iTrader: (7)

Right, and from my understanding, the torque produced by a larger rotor contributes more to pedal feel than to actual stopping distance.

MR.Wicked

so brake fade doesn't contribute to stopping distance....I don't think you were listening.

ambystom01

iTrader: (7)

Do you experience brake fade after a single stop? Unless you're driving a 1984 Lada I doubt you'll experience brake fade while performing a single panic stop. That is what we are discussing here. If you're racing, brake fade is a legitimate concern but that is a cooling issue, not a brake force issue.

MR.Wicked

I get all the heat transfer business. And the modulation business and even the pad material and area business but as a package when driven aggressively as I do in a heavy AWD machine bigger brakes will stop you quicker. Or maybe I have been eating crazy pills.

MR.Wicked

I am not talking about a single stop

MR.Wicked

and nice Clarkson Lada reference...

ambystom01

iTrader: (7)

If you're driving so aggressively on the street as to need a BBK, you should have your license taken away. BBKs do nothing for a daily driver if driven by a sane person.

MR.Wicked

Wow I wasnt being insulting but you had to go there Charming....

ambystom01

iTrader: (7)

If you openly admit to driving so hard on the street that you need brake equipment usually reserved for race cars, you should expect to be called on it.

ambystom01

iTrader: (7)

It's illegal for a reason.