Brake Slotting

[Itachi]

So I've been thinking about slotting my rotors to give them a bit more bite.

I'm making the assumption that it will be cheaper than getting new rotors.

I was hoping to end up with something like this:
(sourced from Aspir3's garage)
http://clubcj.net/garage.php?mode=view_gallery_item&type=garage_mod&image_id=3474

Does anyone know a good place to get this done in Perth?

[spareparts]

i would buy / did buy a set of dba's... yea cost a lil more but they are so much better. the kangaroo paw cooling system in the center of the rottor will keep it cooler to. i have got 80 tho out of my wh statesman rotors with heavy driven and they only just startin to shack under braken but i mean just will get another 20 tho b4 mechening is needed. and commo warp rotors like its goin out of style ant teh stato is just a over waight commo

[aspir3]

David I got mine done by a guy who has a NC milling machine in his back yard. He was really reasonable priced. You can try any machine shop as they should be able to do it..

I hope that helps your search.

[Itachi]

Thanks Troy, yours look really good, so far I have just been looking for brake shops but thought I would consult the CCJ think-tank before I made a mistake

Have you found that slotting them has made any difference in the braking performance?

[Itachi]

Sean, what series of DBA did you get? street, 4000 or 5000?

My car is still a toddler so was hoping to just make a minor mod and see some benefits, when the rotors go I will be upgrading to proper slotted rotors.

[aspir3]

Yes when i roll my car down the drive way on Sunday's it stops really good. Lucky for me my driveway is almost flat so i dont pick up too much speed.

Look I dont drive the car that hard. I would not recommend any one drives their car on the edge around the streets. They are suppose to assist by stopping air pockets between your pads and discs. They will wear your pads out quicker and possible weaken your discs and crack. I just want to worn you of the risks. I dont believe it will happen obviously or I would not have machined them.

I also now have slotted the rears the same as the front. I slotted them for looks rather then performance, but I suspect, yes they would brake better now especially in track conditions.

I paid $20 a disc to have the curve slots machined in. I had to remove and assemble them myself of course. $80 for all 4 I think was cheap. I suspect most would charge over double that but it is still cheaper then new discs.

[Itachi]

Thanks for the info Troy

I don't like the sound of my disks cracking... :S I thought that was more when you get the drilled disks...

For the record this has come on my radar because I went to a track day and plan on going to many more so it is not for street use (unless in an emergency ofcourse).

I think if I could get it done for $200 then I would be happy, unfortunately I don't have the skills to remove them myself so that would probably cost more. I believe new disks will set me back around $600? That is just for fronts and including labour, which is a bit much for me right now with everything else I want to do.

[Dire]

David,
RPW has front slotted RDA's for $210.

I may have found them/similar even cheaper than that but I can't remember now and they weren't in Perth so + postage.

[Itachi]

David at RPW was the one who said he could get them on the car for around $600, it was quite some time ago so not sure if that was front and rear or just front. I vaguely remember it being just fronts though...Also you need to ass GST to the prices on their website so it is actually $230

[aspir3]

David to remove the discs is very easy.
1 remove wheel
2 remove caliper. 2 attachment bolts

Then the calipers fall off at the front. The rears need a little help some times with a soft hammer or wood. And make sure the hand brake is off for the rears.

Yes discs are more likely to crack from drilling then slotting.

The important thing is the slotted grooves should not be too deep and they should be offset on both sides of the discs.

[El-Diablo]

A word for the wary.

Cost of buying properly machined and designed brake rotors is a couple of hundred dollars.

Cost of having some backyard bloke do it on his nc machine can be very expensive indeed.

Some parts of a vehicle should be considered areas best left for professionals.

There is a lot more to brake performance than whacking a few slots on and drilling holes in OEM equipment. Incorrectly placed holes and slots can effect the structural integrity of the brake. Drilling through vanes can affect air flow and reduce brake performance.

Please think carefully before making these sorts of modifications.

[aspir3]

Agreed totally with Rob.

I should have mentioned the guy who machined mine is a car enthusiast like me and does this now for a living now from home. He is experienced at doing this.

He would not drill them as they were likely to crack.

My slots are machined to the depth of the minimum of the disc. So if I machined the discs to minimum thickness then the slots would be gone.

[Dire]

David at RPW was the one who said he could get them on the car for around $600

Thats some BS.
Buy them and get them put on by any old mechanic. Wouldn't cost more than $100, especially if he knows you.

[Itachi]

Thank you for the heads up Rob and Troy, I was always planning to take it to a specialist brake shop and see if they can do it.

Jake, that was an off the cuff quote during a conversation I had with David a while back so the figure may not be accurate, I just remember the $600 figure was thrown around and I felt it wasn't worth it (or I would have done it by now ) I'm also unsure whether it was front and back or just front, maybe David can clear it up for us.

The other problem with the RDA rotors is that from memory (their site is down at the moment for some reason so I can't confirm this) the discs are smaller than the standard VR-X ones.

*EDIT*: On the RPW website (back up again) it says the rotors are 256mm and in the "Big Brake" thread on here the VRX ones are standard at 300mm, so the RDA ones are quite a bit smaller.

I'm not sure if you can just change the rotor size (up or down) as it will still need to fit with the calipers (I am totally clueless about this so it is just me using my "common sense", which may be way off! ) In any case if you can change the size of the rotors, I would be getting bigger ones, not smaller ones.

I think we need a mechanic to join CCJ WA as I have no connections in the motoring scene...