[Gary_C]

The simplest way to break it down is by application and usage.

Primarily street - Drilled
Any significant track usage - Slotted

Originally Posted by sparkyg

1) Rumors are that the drilled can tend to crack for reasons such as too high cooling rate (?) Is this true, was it ever true?

The rumors of drilled rotors cracking come from soo many different sources and schools of thought that it's hard to even know where to begin.

The truth of the matter is that a properly drilled disc, when used with the proper pad compound for the intended use, will last just as long as a smooth or slotted surface disc. In very high temp scenarios a drilled rotor will suffer from more extreme heat cycles which does cause it to wear faster. This is why it's not generally recommended for use with race pads, or extended track sessions.

All discs suffer from the same type of wear with extreme spikes in temperatures, the reason that drilled discs have been known to suffer the most is that the common cracking seen in ALL discs near the end of their life span tend to start at the holes and grow from that point. Rather than acknowledging the root of the problem people simply blamed the hole itself.

2) Drilled brakes appear to be lighter since more material is removed. Is this true? Is the drillling only on the face as it appears to be? Or do the slotted and drilled weigh the same?

Drilled discs are in fact lighter. In a 14" disc is can be almost 1/2 lb.
The discs are drilled on both the inboard and outboard side of the disc.
Each Brembo discs has a specifically engineered drill pattern specific to the discs dimensions and vein structure. Brembo discs have less problems with premature cracking and wear than any other brand.

3) Can one vendors brakes outperform another when they have the exact same size rotor? Is this a case of caliper design, pad material, number of pistons and piston area?

Absolutely. You can only "fake it" for so long and the quality of the product will eventually show through. There are many other brands that offer the same size disc, caliper with the same # of pistons, and make all the same claims as to the benefits of their brake system. It has been proven time and time again that Brembo's build quality is second to none and that is what makes it a better value over the lifetime of the system. You can easily save a few hundred to even a thousand dollars with another brand. But once you start replacing parts, and utilizing their customer service department to help work through problems, you ultimately spend more time and more money trying to achieve what the system should have provided to begin with.

It appears that all the BBK on the forums are drilled? Are drilled really better for street use or is appearance playing a large role?

It really depends on what forums you are looking on. Of all the Brembo kits sold, I would estimate that 60% are primarily street cars with very few that do see real track time, and 40% are consistently at HPDE, Autocross and Club race events.. Of that 60% a good majority are more luxury car or SUV's. This figure is based on the # of kits that leave our doors with slotted vs. drilled discs, and the amount of feedback we get regularly from our dealers who are supporting the consumers who are actively tracking their vehicles.