My Suggestion is Just Don’t Do It!
Just my two cents worth, I am running a full weight 67 Camaro with Global West suspension. I have four piston disk in the front and single piston disk in the rear. I run solid disks; due to the cracking I have experienced with Drilled and slotted disks after only one day at the track. My engine is a 535hp Aluminum Head small block, which places a lot of stress on my system. I have never had a problem with solid disks, and if you get good quality pads, they are already slotted to let the gas out. Pad life is greatly increased by the solid rotors also. I wanted to get you some information from others who are having the same issues, and also a link to a company that has the dimpled disks as an option. They sell all types, and have a good breakdown by your actual needs.
I bet you don't see these pictures in the advertisements!!!
Popular Hotrodding said,
Brake Cooling
Drilled Vs. Slotted Rotors
Posted September 10 2008 08:36 PM by MilesSpeed
Filed under: Tech
There is much debate as to which is best: drilled, slotted, or drilled and slotted rotors.
Here is the debate. When choosing a street/track rotor, is drilled a good thing?
Many brake component manufactures admit that the drillings on the rotors may be more detrimental than helpful if over heated. The edges give heat a place to concentrate and eventually fracture. These cracks aren't huge, but enough to see like on an over-heated flywheel. Slots, on the other hand, are very helpful for dissipating heat, and don't cause the damage the holes do. Most cars on the street will not experience the braking to create the above damage, so they are perfectly fine for street cars.
Race cars though, since many rotors are replaced after each event, can afford the possible cracking due to the holes. The cooling effect is more important.
Drilled rotors may look cool, but if the diameter and thickness of the rotor isn't up to the heat, you may want to reconsider that choice.
http://blogs.popularhotrodding.com/6279 ... index.html
If you feel you want better than just standard Rotors, I would suggest, Diamond Slotted rotors.
http://www.raceshopper.com/sp_rotors.shtml
Diamond Slotted
Recommended for street performance applications. Slotted rotors with a unique diamond etching pattern.
Slotting provides increased brake 'bite' and helps keep pads clean.
Diamond etching gives the effect of Cross-Drilled without any danger of cracking.
Note: Due to the nature of slotted rotors- a slight hum or whirring sound may be evident under heavy braking.
http://www.raceshopper.com/sp_rotors.shtml
From the Honda Boys on HondaSwap.com
Pads still do produce some vapors when they are heated up, a small layer of the pad is going to burn off and that will create vapors.
How-ever, high quality brake pads should have a slot in the surface to allow those vapors to escape. So gas/vapor is not a reason to use cross-drilled brakes.
Cross-drilled brakes, when done correctly WILL increase surface area. (NOT SWEPT AREA, which is different).
It’s simply finding the surface area of a cylinder and removing the top/bottom face.
Surface area = 2*pi*r*h - 2*pi*r^2
If the radius of the drill is equal to the thickness of the rotor, you gain no surface area. If the radius is smaller, you gain surface area. Finally, if the radius is larger you lose surface area.
Example 1:
2 * 3.14 * 8 * 8 – 2 * 3.14 * 8^2 = 401.92 – 401.92 = 0
Example 2:
2 * 3.14 * 6 * 8 – 2 * 3.14 * 6^2 = 301.44 – 225.08 = +76.36
Example 3:
2* 3.14 * 10 * 8 – 2 * 3.14 * 10^2 = 502.4 – 628 = -125.6
Surface area radiates heat, so more surface area does result in faster cooling. However, it is at a sacrifice of MASS, which is what determines your thermal storage.
Cross drilling does not just reduce weight.
However, you would be better off going to a larger rotor which has more surface area and mass. That way you don't have to worry about cracking. The stock Honda rotors don't have a ton of thermal storage to begin with, why drill some away?
Here is the last of some good information. I know the Drilled and slotted thing looks cool, but you may be working against yourself as far as safety and longevity are concerned.
http://www.surrealmirage.com/subaru/bra ... conclusion
Manufacturers of either type make grand claims for performance gains. That's how they sell this snake oil, and they sell a lot of it. The problem is these claims are quite unproven in real world testing. It is worth noting that few full-out racing cars use these types of rotors.
For all intents and purposes drilled or slotted (or both) rotors are appearance, not performance products. Brembo even has a warning on their cross-drilled rotors stating they are not designed for high-speed use!
If you want improved braking, look to higher performance pads and fluid. If you think drilled or slotted rotors make chicks hot for you, get them for that reason. But don't get them for a performance enhancement.