Brake Upgrade Part II - Page 3 - United Bimmer Community

nick_318is · 12-13-2005, 11:09 PM

Good explaination C1apton, I agree completly, i think to know brake fade you have to experience it, the stock brakes on BMWs are very good compared to some other things, my Uncle works for Rouche (sp?) and worked on their mustang and told me how horrible it was (stock) at hard stopping after only 2 or 3 runs.

**///M Power** · 12-14-2005, 12:14 AM

:-/ Trust me cross drilled rotors do barely anything (if nto nothing) to reduce brake fade. It's merely for show.

Brake fade is when basically you are using your brakes a lot of a difficult run and they get so hot for a consistent amount of time that a very thin layer of heat is constantly beign radiated fromt he rotor so that it seems to reduce the grip the pads have on the rotors.

Trust me, Deleware doesnt have canyons like we have. If you didnt abuse downshifting, ud be dead. These runs are known for the amount of bikers who have gone off the cliffs. I have seen more than a few RIP crosses along theroad of these canyon runs. It's not just riding brakes, its the necessity to abuse them. These are the canyons you see all the bikers and crotchrockets on. Where you could EASILY see ferrari's, lambos, maserati's, and of course 40 BMWs in a row.

If you dont think brake fade is a problem, then you obviously have never tracked or done some decent runs.

nick_318is · 12-14-2005, 10:54 AM

Quote:

Originally Posted by ///M Power

If you dont think brake fade is a problem, then you obviously have never tracked or done some decent runs.

**c1apton** · 12-14-2005, 11:26 AM

Quote:

Originally Posted by ///M Power

:-/

Trust me, Deleware doesnt have canyons like we have. If you didnt abuse downshifting, ud be dead. These runs are known for the amount of bikers who have gone off the cliffs. I have seen more than a few RIP crosses along theroad of these canyon runs. It's not just riding brakes, its the necessity to abuse them. .

If you dont think brake fade is a problem, then you obviously have never tracked or done some decent runs.

Your description of these canyons is way too mild. We've been through there a couple of times (in tour buses no less) and we literally crawled through that stretch. It's a bitch -period!

DEATH2000 · 12-14-2005, 12:10 PM

Quote:

Originally Posted by c1apton

Not stupid at all. Brake fade is when you step on the brakes and little or nothing happens. Feels like it wants to grab but doesn't. You have full peddle feeling but it's similar to driving on ice. It happens when hard on brakes (occassionally) or when you're first burnishing in new pads/rotors. That's why they tell you to avoid traffic and hard stops for first 100+miles. Visiting "bud" says " try braking using your clutch peddle. It's like that"

Yea my brakes are kinda like that now. U have to step on the pedal alot before the brakes really grab, i get a fair bit of pedal travel before the brakes bite.

And Nick, is spelled Roush.

**94bmw325i** · 12-14-2005, 02:31 PM

Eric it was a joke, and your response to Delaware even having canyons is crazy. Delaware is on the east coast, all we have is a bunch of back roads with lots of twists, and you could crash into a river, not fall 100 ft below.

Storamin · 12-14-2005, 06:06 PM

Quote:

Originally Posted by ///M Power

Maybe you dont know what Mullohand Drive is. It's one of the msot difficult canyon runs in SoCal that I can find. It's 25 minutes of nonstop 2nd/3rd gear blind turn where its either go off a cliff or hit gravel/side of mountain. It's a very difficult run that leaves everyone friggin tired. On the last two 30-45 Bimmer meets that have gone on Mullhand, there have been an accident both times. One guy needed new brake fluid and he had a lto of brake fade, lost brakign power, and almost went off the cliff. On a recent one a e46 had brake fade and tapped the e46 in front of him. Most people would think peopel are makign up excuses to say they have brake fade to hide guilt in a accident, but if youve ever been ont hese runs youd believe them. No matter wut u do, u defintely take full advantage of those short straightways where you can hopefully cool down your brakes enough for another set.

That sounds like a track on a cliff! I can see how you'd get brake fade there. There's really nothing you can do short of running race pads or a BBK to fix your problem, though.

**///M Power** · 12-14-2005, 09:31 PM

Vented rotors do help somewhat

**brien4787** · 12-16-2005, 05:57 PM

Don't kill anyone ///M Power

Storamin · 12-29-2005, 07:01 AM

http://forums.bimmerforums.com/forum...d.php?t=460301

That thing cracked like a son of a bitch. Man, I bet he's feeling great he went for that extra "performance" option of cross drilled.

**///Menace328i** · 12-29-2005, 01:28 PM

Quote:

Originally Posted by Storamin

http://forums.bimmerforums.com/forum...d.php?t=460301

That thing cracked like a son of a bitch. Man, I bet he's feeling great he went for that extra "performance" option of cross drilled.

Wow goog thing I just whent with the slotted... not the crossdrilled by tony's shop rotors that cost $50 a pair....

**jybute** · 12-29-2005, 10:05 PM

vented or cross drilled rotors would only prevent heat. chances are you will find vented or cross drilled rotors on an oversized rotor, but because of the amount of space wasted by the vents, or drilled holes you will not get better stoping power, the only time you will get better stopping power is when you have oversized blanks, or when youve been doing a canyon run that heats up your regular rotors, and your cross drilled/vented rotors then serve their purpose. and even then i think you would have to be pushing your car to the limits to see the benefits of crossdrilled/vented rotors.
but they sure do look good.

Storamin · 12-31-2005, 02:42 PM

http://forums.bimmerforums.com/forum...d.php?t=461019

Take it from the experts -- people that actually race their cars.

**RealBmw 02** · 12-31-2005, 04:59 PM

Look at it this way....

The amount of friction that your brakes can generate is dependent on surface area, the coefficient of friction between the pads and the rotor, and the clamping force of the caliper.

If you assume no change in pad or caliper clamping force, then braking frictional force is directly related to surface area. Therefore the rotor that has the greatest surface area will yield the best stopping force for a controlled test.

However, when you are making repeated heavy stops from high speeds, the brakes are going to get extremely hot. Heat is your enemy here so keeping the brakes cooled becomes a very important task. This is where you will find benefits from slotted rotors. They will be able to dissipate the heat faster therefore reducing the chances of fading late into the race (or canyon run).

You have to look at your cars application. If you intend of autocrossing there is little chance that you will heat up your brakes enough in one run to induce brake fade. If you intend on tracking your car you might need to upgrade to slotted rotors because repeated hard laps will cause stock (blanks) to overheat and fail.

**///Menace328i** · 12-31-2005, 07:41 PM

Quote:

Originally Posted by RealBmw 02

Look at it this way....

The amount of friction that your brakes can generate is dependent on surface area, the coefficient of friction between the pads and the rotor, and the clamping force of the caliper.

If you assume no change in pad or caliper clamping force, then braking frictional force is directly related to surface area. Therefore the rotor that has the greatest surface area will yield the best stopping force for a controlled test.

However, when you are making repeated heavy stops from high speeds, the brakes are going to get extremely hot. Heat is your enemy here so keeping the brakes cooled becomes a very important task. This is where you will find benefits from slotted rotors. They will be able to dissipate the heat faster therefore reducing the chances of fading late into the race (or canyon run).

You have to look at your cars application. If you intend of autocrossing there is little chance that you will heat up your brakes enough in one run to induce brake fade. If you intend on tracking your car you might need to upgrade to slotted rotors because repeated hard laps will cause stock (blanks) to overheat and fail.

there you go, and please can we put this to rest already with this beneficial tech tip. admit it, vented rotors are not useless, they do have benefits, and they also look good, if you have had some crack on you is because you get what you paid for, I had good ones with good results that's why I'm using the same application on my BMW. Plus they look good to.