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      01-21-2012, 08:44 PM   #23
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congrats, now we're all saying the same thing over and over again
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      01-21-2012, 08:54 PM   #24
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Everybody agreeing, isn't that a miracle
Also, that helps me process the information.

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congrats, now we're all saying the same thing over and over again
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      01-22-2012, 02:11 AM   #25
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BBK's are a total waste of money

Now we're arguing again, eh?
I'm just kidding lolol..just bored.

I want BBKs, but I technically don't need them just yet. For now, pads, fluid, and lines are plenty good enough
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      01-22-2012, 03:27 AM   #26
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Stock M brakes are pretty good. I get some brake fade after running canyons for a few hours. It's probably time for me to upgrade.


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Originally Posted by mfanatic325 View Post
BBK's are a total waste of money

Now we're arguing again, eh?
I'm just kidding lolol..just bored.

I want BBKs, but I technically don't need them just yet. For now, pads, fluid, and lines are plenty good enough
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      01-22-2012, 07:33 PM   #27
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Quote:
Originally Posted by The HACK View Post
The benefit to a multi-piston FIXED caliper system is not the clamping force, since a properly engineered system SHOULD have roughly the same piston area as a stock system, otherwise your brake pedal would be all f**ked up. If the aftermarket system has a larger overall piston area than stock, the brake pedal would be soft/mushy feelie. If the aftermarket system has LESS piston area, the pedal would be ROCK HARD to press.

The benefit to a multi-piston caliper is two-fold. First, the same piston area is spread out onto multiple surfaces, thus allowing the engineers to build a system that spread out the forces applied evenly to prevent flex or twist in the brake pad. Second, a rigid, fixed caliper design has less flex. Both of which contribute to a more precise brake control and modulation compared to stock sliding caliper design. However, the pads must be longer in shape to accommodate the spread-out piston pattern, leading to a smaller sweep area.

Another "benefit" to a fixed style caliper is that since the mount is fixed and rigid, the caliper bodies can be constructed out of aluminum to save weight. Typical 4 or 6 pot calipers can weigh a few lbs lighter than the stock iron caliper since the bracketry required to mount a fixed caliper is much lighter and smaller.

Since brake rotors discs can only be made of iron or exotic material like ceramic composite for their heat dissipation properties and strength, a single piece rotor will weigh more than compound rotors. Compound or 2 piece rotors can have the hub area be constructed of a lighter material, typically aluminum, and saving quite a few lbs. especially custom constructed kits that uses a multi-piston fixed calipers, where the sweeping area is drastically reduced from the stock sliding caliper design, so the rotor rings can be constructed to be much shorter and the hub area increased to further reduce weight.

In addition, 2 piece rotors can be designed to separate the rotor disc away from the rotor hub. There are multiple benefits to this as well, a hub separated from the heat sink that is the iron rotor will prevent heat from being transferred directly to the wheel bearing, prolonging the life of the bearing in a race application. Additionally, separating the hub and the heat sink allows the rotor to expand and contract independently from heat to prevent stress cracks and warpage. Lastly, the physical separation of the disc and hub allows for an open area where the internal cooling vanes of a vented rotor to draw in more ambient air thus allowing for a more efficient cooling. The only drawback to 2 piece floating rotors is that they're very expensive to make.
I owe you a beer. This is the kind of comprehensive info that takes me hours to find elsewhere.
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      01-25-2012, 11:23 PM   #28
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Quote:
Originally Posted by philippelyp View Post
Is the total pad contact surface area larger in a BBK even if the sweep area is smaller?
Depends on what the shape of the pad is and how the pistons are laid out, I suppose. A properly engineered brake system will likely take into account that the braking force applied is a function of the overall friction area times friction coefficient times the perpendicular force applied by the piston(s). However, there's just no way to engineer a different system based on hundreds of different make and models, so most aftermarket big brake providers will likely just engineer a handful of pad shapes, and alter the system's performance parameters via piston size and rotor size.

Ultimately, the biggest determining factor of how well your brake system will work, be it a BBK or a sliding caliper on one piece rotor, is entirely dependent on the grip your tires provide, and the system's capability to dissipate heat. It's as simple as that. How the engineers compromise each component to achieve the best performance, is the voodoo science we all pay the engineers so much for.
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      02-01-2012, 08:29 PM   #29
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With all that information I ordered my BBK yesterday. I went for a 4 pistons StopTech kit with 332mm slotted rotors for the front. I'm also changing the rear pads to StopTech to have matching compound (not sure if that really matters but a couple of people told me so) and changing the rear rotors to slotted R1 Concept and switching to ATE brake fluid.
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      05-10-2019, 03:20 PM   #30
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wow...

This is the answer I needed... 7 years later
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