Q's: Crossed Drilled Rotors and Ceramic Pads - Land Rovers Only

2007 LR3 SE · 08-10-2009, 02:24 PM

Have been reading this site for a while, but this is my first posting.

I’ve got a 2008 LR3 with 24k mi. and it is in need of a brake job. The local British shop will do the work for only a $150, which will work out well because of my busy work schedule.

Since I need to replace the rotors and pads, I was thinking about putting on higher performance crossed drilled & slotted rotors, along with ceramic pads. I know it’s not a high performance street machine, but I thought that the cross drilling will dissipate water faster when water fording or driving in the rain. In addition, when four wheeling in rough terrain, I thought the cross drilling would keep the brakes cooler.

Additionally, I’m thinking of using low temperature ceramic pads for 2 reasons: less brake dust and won’t compromise brake power, at least that’s what I think. Any thoughts? ? ? Brakeworld.com shows a good set by “Disk Italia” that is both cross drilled and slotted. They also have Ceramic Pads that fit. Here’s a link Brakeworld

Have any of you out there done this type of conversion or know someone who has? ?

Cheers

mbrummal · 08-10-2009, 05:20 PM

Actually, cross drilling and slotting don't help dissipate heat at all. they just reduce the area the pad touches. The only thing they really do is help dissipate any gasses created by braking therefore preventing the pad from "floating" on the gasses.

Just some food for thought.

2007 LR3 SE · 08-10-2009, 05:31 PM

Yes, you're right. I was typing that posting while I was on the phone and didn't really think the statement through. But I was thinking that the cross drilling would allow them to expel water faster in heavy water condition (river crossing, etc.). And, my other thought was that ceramic pads would reduce the heavy brake dust. Have you tried ceramic pads or cross drilled rotors on an LR3??? I don't know how it will function.............

mbrummal · 08-10-2009, 05:34 PM

Getting water out of the rotors shouldn't be much of a concern at all. You could try ceramic pads but they won't work all that well until they are warmed up. (You would just have to push harder)

2007 LR3 SE · 08-10-2009, 05:45 PM

My other car is a Mercedes C Class AMG, and I put ceramic pads on it. They were a low temp ceramic (brand: "Rotex") that did not require the usual "warming-up" of traditional track oriented ceramic pads. They stopped the car when cold almost exactly the same as the OEM, but they had significantly less brake dust. My concern in using similar pads on the LR3 is that it weighs almost twice my Mercedes.......

mbrummal · 08-10-2009, 05:55 PM

Quote:

Originally Posted by 2007 LR3 SE

My other car is a Mercedes C Class AMG, and I put ceramic pads on it. They were a low temp ceramic (brand: "Rotex") that did not require the usual "warming-up" of traditional track oriented ceramic pads. They stopped the car when cold almost exactly the same as the OEM, but they had significantly less brake dust. My concern in using similar pads on the LR3 is that it weighs almost twice my Mercedes.......

shouldn't be much of a problem unless you overheat them going down a mountain road or something.

Disco Mike · 08-10-2009, 06:29 PM

First, good slotted and drilled rotors, like DBA's do dissapate heat by allowing hot gases to not get between the pad and rotor, allowing for better stopping power.
Make sure to use a synthetic DOT 4 fluid for better results and look more towards EBC, Green Stuff, be it the 600 or 7000 series for less dust and better stopping power.

mbrummal · 08-10-2009, 06:45 PM

Quote:

Originally Posted by Disco Mike

... slotted and drilled rotors... do dissapate heat by allowing hot gases to not get between the pad and rotor, allowing for better stopping power.

better stopping power because of more contact, yes. More heat dissipation, no.

The slots/holes only let the gasses move from between the rotor and pad, nothing more. Not enough air moves through the holes to make a difference. Most of the heat is dissipated through the center of the disk in the vanes. They are designed to draw air from the center and expel it around the perimeter. Only a little heat is transferred to the air from the surface of the disk.

The holes reduce the thermal capacity of the disk and unless the holes are cast into the rotor, they create many unwanted stress risers in the disk.

Here is some great information on brakes.
StopTech : Balanced Brake Upgrades

h2oland · 08-14-2009, 03:24 PM

my response is purely out of curiosity, but wouldnt the faster escape of gasses decrease pressure thus decreasing temp at least a little? Or since there is no "floating" happening does then contact friction maintain temp depsite the gas escape?

Disco Mike · 08-14-2009, 07:48 PM

I have nearly 80,000 miles on my DBA's and they will still out stop a non-drilled/slotted rotor.
Part of the trick is to not buy the cheap rotors, yes, they will crack based on their cheap alloy.
Yes the brakes get hotter, that is why I always tell everyone to use synthetic brake fluid, but I can out stop you.
You can not expect brakes, as small as our are, to stop quicker without more heat build up. People buy DBA's to stop quicker and harder and are not worrying about heat.