Zimmerman X-Drilled Rotors???

[JordanW]

I'm just making sure here...

I am installing a set of Zimmerman x-drilled rotors ( 86 351 401 05) on the front of a 2001 Boxster. Both rotors in the box have the drilled holes in the same angle. Other rotors I've installed (on other cars) that were X-drilled and/or slotted were different for left and right. Does anyone know if that is or SHOULD be the case for the Zimmerman ones? It appears the rotation is correct on the right side, but on the left not so much?

Insights appreciated or any helpful resources, I'm not finding much by searching.

Thank you!

[hosickjg]

Yes, this is correct. Zimmerman does not make a left and right. One of your rotors drill patterns will run the opposite way. Its a little strange.

As a side note, after using them for a couple months post some feedback on them.

I bought a set a year ago and have been VERY dissapointed with them. They started to warp in a matter of 5 months. If I drive aggressively they warp as soon as you heat them up a bit. I found this very dissapointing because thats the point to having X-drilled rotors (to disperse gas and heat to reduce the risk of warping and increase braking ability).
Interested in hearing if anyone else has had these issues or if I just got a bad pair.

[JJ 911SC]

Originally Posted by hosickjg

... One of your rotors drill patterns will run the opposite way...

but look ok when in reverse

[JMatta]

They started to warp in a matter of 5 months.

Did you bed the new pads properly? Warpage or pulsing is usually an indication of pad material buildup from improperly bedded brake pads.

[hosickjg]

Originally Posted by JMatta

They started to warp in a matter of 5 months.

Did you bed the new pads properly? Warpage or pulsing is usually an indication of pad material buildup from improperly bedded brake pads.

Yes, they were broke in properly.

Your quite correct that most people have buildup that makes them think that their rotors are warped when they are not.
We took the car out for a good run one day and pulled the drives side wheel off it right away while the rotor was still hot. You can actually see the difference in space between the caliper and rotor change as you turn the hub while the rotors are hot. The drivers side rotor Definitely is visibly warped when warm.

And before someone says it, YES the wheels have always been put on with a torque wrench and torqued properly.

[Wayne 962]

There are lots of things that can damage rotors. One that some people don't realize is simply putting and holding the brake pedal on a super-hot rotor. If you come in off of the track, and then sit in pit row for a minute or two with your foot on the pedal, when you pull out, you might find that your rotors have been warped. This is because the heat concentration builds up in the pad contact area, and you're sitting there with your foot down just cooking the rotor like a pancake. If you come down off a mountain riding the brake, and then sit at a traffic light at the end, then you will have a good chance of warping them.

-Wayne

[JJ 911SC]

Wayne

Thanks for the tip. As a Quebécer trained driver, we don't got not much use for the brake pedal , so they should be perfect.

PM send on related mater.

J.J.