Madness Shop Manual

Zen and the Art of reverse automotive engineering

  • Article Types

  • Popular Articles

  • Past Articles

Drilled, Slotted, or Blanked Rotors?

Posted by Mad Scientist on March 23, 2008

CRX1.0 rotorsDiscussions about brake rotors are as heated about comparing Nissan to Honda. Wilwood, Brembo, or Fastbrakes, the question always boils down to ‘what performance options are worthwhile?’. Well, this basically breaks down to a few different categories.

Drilled

Drilling metal weakens it, and magnifies inconsistencies in the metal. This means that your rotors are more likely to warp. Also, the holes themselves are now missing from your contact patch, meaning that you have less effective braking power. The second downside is that holes are always the weakest point of the rotor, meaning that cracks are more likely to form, especially under heavy braking.

Cracked rotor`

The exception to this is Porsche rotors, since they are cast with holes, rather than being drilled. It’s a great way to set yourself apart from the competition, but the slots only help to prevent brake fade. Another variant of the drilled rotors is dimpled rotors, which offer the same pros and cons.

Slotted

Slotted rotors were the hottest thing available for hot rods. They’re not so great for street cars. As long as the slots are shallow and close (if there are more than 5 slotted channels on one rotor, they’re close) you’ll get good braking response along with decent heat dissipation. If you simply must have that import-tuner look on your car, slotted rotors are the way to go. Just make sure that the slots don’t extend to the edge of the rotor. The inner and outer edges of the rotor should be solid, with no metal cut out of them.

Blanks

Brembo Blanks are what I suggest for everyone who asks. They’re inexpensive, they’re very effective, and they’ll work well with whatever pads you use. If you’re racing on a track, you’ll want a little more heat dissipation, but in all reality, you should have two separate sets of front rotors: street & track.

Happy tuning, and take lots of pictures!

Leave a Reply

XHTML: You can use these tags: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>