Flat or drilled?

4to8m8 · 4to8m8's Garage

Picked up a couple Zimmerman drilled rotors the other day for a brake project. Now I'm reading how the drilled rotors are prone to cracking and that they are noisy. Should I just leave my Carrera stock rotors on? (3 DE's a year).

chuckr · 11-23-2005, 06:41 AM

From what I have seen, the drilled rotors will crack after a while
under heavy track use. I run the Zimmerman drilled on my 89
and I don't have any noise issues and really good stopping
power, no fade and great looks.

Joeaksa · 11-23-2005, 06:53 AM

Same here. No problems at all but I do not track the car.

JoeA

4to8m8 · 4to8m8's Garage

Hmmm, Maybe I'll procede with the rotor swap.

Emission · Emission's Garage

My drilled are cracked (track use). No big deal as the cracks are tiny hairlines... bigger, and you have to replace the rotors.

I don't know what the "actual" benefits of drilled rotors are (cooling, less gas between pad and rotor, etc...), but I hear slotted are the best of both worlds.

Bill Verburg · Bill Verburg's Garage

The smaller rotors used oem on SC and Carrera were never meant to have holes in them. The ones that are available are a marketing gimmick only, they will crack more quickly than sole od slotted.

Any rotor can be made to crack if abused enough, and the small cracks will only get bigger.

To increase longevity keep them cool.

Emission · Emission's Garage

Quote:

Originally posted by Bill Verburg
To increase longevity keep them cool.

True.

I cracked mine the first time I abused them on the track. Now, I have 993 deflectors and no splash guards on the back of the rotor - the cracks aren't growing, and the car stops much better.

Keep 'em cool.