[Dave-ROR]

Originally Posted by Type[R]+

Lol @ this thread. Everyone's a brake expert now.....

Well your arguement fails on physics alone.. but here are what some brake experts say (heck they even make and sell swiss cheese rotors! These companies use to take an even stronger stance against them, but I guess when you can remove material from a blank and sell it for 3-5x as much money....):

Originally Posted by wilwood

PSlots or grooves in rotor faces are partly a carryover from the days of asbestos pads. Asbestos and other organic pads were prone to “glazing” and the slots tended to help “scrape or de-glaze” them. Also, cross-drilling and/or slotting the rotor for racing purposes was beneficial by providing a way to expel the gasses created when the bonding agents employed to manufacture the pads began to break down at extreme temperatures. This condition is often referred to as “outgassing.” When it does occur, the driver still has a good firm brake pedal, but a significant reduction in friction. Normally this only happens at temperatures witnessed in racing. However, with today’s race pad technology, “outgassing” is no longer a concern with pads designed for racing.

So in the final analysis, drilling and slotting rotors has become popular in street applications for their pure aesthetic value. Wilwood provides rotors slotted, drilled or plain. For most performance applications, slotted is the preferred choice. With certain pad material, slotting can help wipe away debris from between the pad and rotor as well as increasing the coefficient of friction between the rotor and the pad. A drilled rotor provides the same type of benefit, but is more susceptible to cracking under severe usage; however, for street and occasional light duty track use, they will work fine. For more severe applications, we recommend slotted rotors.

Originally Posted by stoptech

For many years most racing rotors were drilled. There were two reasons - the holes gave the "fireband" boundary layer of gasses and particulate matter someplace to go and the edges of the holes gave the pad a better "bite".

Unfortunately the drilled holes also reduced the thermal capacity of the discs and served as very effective "stress raisers" significantly decreasing disc life. Improvements in friction materials have pretty much made the drilled rotor a thing of the past in racing. Most racing rotors currently feature a series of tangential slots or channels that serve the same purpose without the attendant disadvantages.

Originally Posted by Baer

What are the benefits to Crossdrilling, Slotting, and Zinc-Washing my rotors?

In years past, crossdrilling and/or Slotting the rotor for racing purposes was beneficial by providing a way to expel the gasses created when the bonding agents employed to manufacture the pads...However, with today’s race pad technology, ‘outgassing’ is no longer much of a concern...Slotted surfaces are what Baer recommends for track only use. Slotted only rotors are offered as an option for any of Baer’s offerings.

Originally Posted by GRM-Not as expert but...

Crossdrilling your rotors might look neat, but what is it really doing for you? Well, unless your car is using brake pads from the '40s and 50s, not a whole lot. Rotors were first drilled because early brake pad materials gave off gasses when heated to racing temperatures, a process known as "gassing out." ...It was an effective solution, but today's friction materials do not exhibit the some gassing out phenomenon as the early pads. Contrary to popular belief, they don't lower temperatures. (In fact, by removing weight from the rotor, they can actually cause temperatures to increase a little.) These holes create stress risers that allow the rotor to crack sooner, and make a mess of brake pads--sort of like a cheese grater rubbing against them at every stop. Want more evidence? Look at NASCAR or F1. You would think that if drilling holes in the rotor was the hot ticket, these teams would be doing it...Slotting rotors, on the other hand, might be a consideration if your sanctioning body allows for it. Cutting thin slots across the face of the rotor can actually help to clean the face of the brake pads over time, helping to reduce the glazing often found during high-speed use which can lower the coefficient of friction. While there may still be a small concern over creating stress risers in the face of the rotor, if the slots are shallow and cut properly, the trade-off appears to be worth the risk.

And note that lots of slotted rotors and just cut into the rotor, unlike the rounded edges on NASCAR rotors (the NASCAR way is proper).

This isn't rocket science. The friction generates a TON of heat, you want a large solid heatsink to take that heat from the pads and calipers and then remove it through the air (the rotors job after generating friction with the pad AND dissipating heat from the pads/caliper).

Do you also believe that in a properly balanced brake system that switching to rotors 2-3" larger and huge calipers actually stop braking distances too with no regard for brake bias/balance?