Any caliper upgrades out there that use the stock rotors?

[Dieselino]

Anyone know of any caliper upgrades that work with the factory rotors? The factory rotors are a good design and size, the calipers however are a different story.

[Radiation Joe]

The calipers are fine. They could use solid bushings, but otherwise are fine for all but endurance racing.

The rotors, on the other hand have inadequate cooling due to the way the rotor is connected to the hat with pins.

If you want a brake upgrade, just go to the Bimmerworld website and get the Performance Friction kit.

[SV Concepts II]

A solid brake upgrade would be some premium Stoptech/Centric (ie: our Frenetiks) slotted (drilled if you do not track) rotors with SS brake lines, synthetic fluid and some good aftermarket pads such as Hawk HPS, Porterfields, Stoptech St. Performance, Cool Carbon, etc etc

[Technic]

Originally Posted by Radiation Joe

The calipers are fine. They could use solid bushings, but otherwise are fine for all but endurance racing.

The rotors, on the other hand have inadequate cooling due to the way the rotor is connected to the hat with pins.

If you want a brake upgrade, just go to the Bimmerworld website and get the Performance Friction kit.

The whole purpose of an aluminum hat with an iron/steel rotor suspended with pins is for cooling/heat dissipation... the same idea used in all BBK floating rotors.

[AP Racing - Chris_B]

Originally Posted by Technic

The whole purpose of an aluminum hat with an iron/steel rotor suspended with pins is for cooling/heat dissipation... the same idea used in all BBK floating rotors.

Actually, the whole idea originally centered around a decoupling of thermal distortion. In extreme situations (which very few road cars will ever experience) the iron gets hot enough and spins fast enough to expand at a different rate than the rest of the rotor. Using an aluminum hat with floating attachment, the rotor is now free to expand on its own without constraint on one side. This avoids the "coning" that can take place with a 1-piece rotor as the hat section would essentially hold one side of the rotor with the other side being free to grow. Again, the chances of a street car ever seeing this happen are remote outside of serious track duty.

If the aluminum hat is not bolted solid to the iron disc, the advantages of heat dissipation are lost. This is one of the advantages to a strap drive disc assembly over a traditional full-floating assembly. The straps serve as another thermal conductivity path, although certainly not better than a bolted 2-piece arrangement. However, decoupling is achieved with no moving parts, rattling or periodic maintenance.

Chris

[Radiation Joe]

Originally Posted by Technic

The whole purpose of an aluminum hat with an iron/steel rotor suspended with pins is for cooling/heat dissipation... the same idea used in all BBK floating rotors.

This is incorrect. The pin style of mounting the rotor to the hat severely restricts air flow to the disk. Two piece rotors from Brembo, AP, Performance Friction, Stoptech, etc., all use a mounting technique that leaves the vanes relatively unobstructed. This provides superior cooling to the OEM design.

The Audi RS6 used huge rotors with 8 piston Brembo brakes and had horrendous brake overheating issues. As soon as we replaced the pin type rotors with a conventional design, the majority of overheating problems went away.