Hi All,

I have a custom set up for the fronts that include Porsche Boxster calipers with 300M rotors. Everything went together ok but I am getting the very, very loud squeel when I brake unless I wait and slam on the brakes. Any type of light brake pressure and you can hear me coming a mile away. I have changed the pads 3 times so at this point I know it definately isn't the pads. If there are any brake guru's out there willing to take a look at I would appreciate it. The brakes work very well in stopping but if I can't get rid of the noise I may have to put the stock brakes back in which defeats the purpose of the upgrade.

Sorry not sure how to post pictures of the setup.

Again if anyone has any ideas and is willing to take a look it would be much appreciated.

Thanks

Sue

Are you running the proper shims and/or fitting?
Can you see any unusual wear in the rotors? Even the slightest groove could be your answer as to where the noise is coming from.

Hello Sue. Long time since we heard from you.

I would think that your new set up either needs some Shims Between the Brake Pads and the Piston(s) or some of the Brake Quiet goo, basicly something to reduce the Brake Pads vibrations.

I wish that I could help but I'm very busy these days. Any good mechanic or DSMer could help.

Ghislain.

Hi Tyler,

The rotors are brand new and I know the mechanic has inspected them for unusual wear. Shims though, hmmm.....

Hey Ghislain,

No worries I know if you could you would take a look at them yourself you would.

I haven't looked into shims between the pads and the pistons as they are Porsche calipers running Porsche pads. We tried brake goo as well as some other stuff that was sprayed on the rotors. Unfortunately it didn't help. Within 30 mins of driving the car the noise was back.

I will see about shims and let you know how it goes.

Thanks guys

Tried shimming and that didn't help. Any other suggestions?
Other than changing brand new rotors I'm not sure what else to do.

Help please....

Hopefully this won't be "too obvious".
But are you simply running a squeaky setup?

Case In Point: I run 4 piston Wilwood fronts, running on larger Wilwood 13" brakes. If I use a pad that's more aggressive (read: for racing), there's squeal regardless of what I do at 'slow down' speeds (small pushes of the pedal). There's just no way to avoid it, without getting a softer pad.

You can reduce it by hard seating of the pads, but even that can't help if you're using a hard racing-type compound. A good shop (like Marken Performance of KW) can tell you what level of pad will produce what level of brake dust and noise.

Hi Michael,

I'm using stock Porsche pads which aren't that agressive. I have used more agressive pads on the stock setup which were noisy. This noise is multiplied by 100. Sounds like an exaggeration and I wish it was. You can hear me breaking a block away. I'm going to try a new set of rotors and hope it will cure the problem.
If it doesn't work do you think the shop you mentioned would be willing to take a look at the set up?

How are your brakes by the way? Sounds like an impressive set up.

Thanks

Sue

Ok guys tried new 300M rotors and no luck.

I'm at the point where I may have to take this setup off and go back to stock or I can see if a 2 piece rotor set up with 12 inch rotors would do the trick. The problem is is I may be throwing good money after bad and it might be time to throw in the towel.

If anyone has extensive experience with brake dynamics and would be willing to take a look I would really appreciate it.

Thanks

So you have tried the difference. I just didn't want to leave the obvious unasked.

They work well. I believe Peacock is also running the 4-piston Wilwoods, and once you go with that, you can never go back I'm sure the Porsche are the same way. They can grind you to a chest-against-seatbelt hurting stop.

I have a friend with a GT2, I'll ask him if he's had the problem, or how they fix brake squeal.

What about just getting the rotors turned on a lathe, take off any ridges or glazing.

oops nevermind I see you tried new rotors..

Did you try applying the brake pad goop? and/or lubricating the sliders? Vibrations are what causes the squealing as far as I know.

Thanks Michael.


Hi Adam,

The 1st set of rotors we machined, same noise so we went with a brand new set and the same exact noise. When new pads are just put on or new rotors there is no noise. Usually by 50kms it gradually builds up until it is back full volume.

Mmmm, noise comes back after the Pads get broken in... Very obscur.

I wish that a good T.O. DSM'er would step in to hav a look at it for ya.

Check your pm.

Ghislain.

Hi Adam,

We tried brake goop and some stuff that you spray on the rotors. It helped a bit. I almost made it home before the noise came back. We even machined the knuckles to ensure a flat surface for mounting.

There seems to be some issue between the pads and the rotors but we just can't figure it out.

are there slots or cross drills in the rotors?

If the pads are meant for slotted or drilled rotors and the rotors are not then you could be getting a build up of brake dust in there.

I believe the stock Boxster rotors are cross drilled. Going on one of the Porsche sites I do believe normal blanks have been used without any problems. I could probably have the rotors sent out to be crossed drilled. I know it isn't recommended but at this point it might be a cheaper solution for me since I now have two sets of rotors.

Thanks

If you are sending them out, I would suggest having them slotted rather than cross drilled..

Hi Ziggy,

I may have to stick to cross drilled in this case to try and keep it as similar the Porsche set up as possible.

I have heard that cross drilling can lead to cracking, and if you are having vibration problems, that can only make it worse. The other recommendation I would then make is to have them "dimpled" but not drilled through....

Drilling can lead to cracking. I have changed rotors that were drilled and when they came off the car had a whole heap of spider cracks running through them. That's why I don't bother with it now, that and the fact that it costs more.
Dimpling... hadn't thought of that.
At this point though I'll do almost anything in order to eliminate the brake noise. The problem is I don't know what is causing it. If it means I have to use drilled rotors and change them more often then so be it. Might be a reason for me to get my rotors from you

Thats a Nick Boers brake package is it not? Maybe he can give you a suggestion.

Hi Jerry,

I am using Nick's brackets. I was speaking with a Porsche guy that designed a similar set up for a 2G and he recommended I use anti vibration dampers that can be ordered from Porsche. I should know by tomorrow if it works or not. If it still doesn't work Nick has agreed to take a look to see if he can determine what difference, if any, is between his set up and mine.

Just to give everyone a quick update.. The pads were chamfered and the dampers installed. Unfortunately the noise is still there but if I am braking and keep an equal force I can stop without noise. If for some reason I am braking and lessen the initial force applied but I'm still on the brakes the noise occurs. At this point I am going to give this a rest. A least I can drive the car now without attracting everyones attention when I brake. The pads currently the full surface isn't making contact with the rotors I'm hoping as I bed them in the noise will go completely away.

I want to thank everyone that replied in order to help me fix the problem

Thanks it is really appreaciated.

Sue

are the edges of the pads tapered? as when i used non tapered pads they clearly produces more noise \___/ proflie like this or |__| this?

The edges were definately chamfered. Currently only one side makes noise and that is if it is cold or wet. When the pads are warm I only get a little noise from that one side.

Are the 300M rotors the same thickness? Are the relocation brakes keeping the calipers concetric with the rotation of the rotors. I think the pads are "scrubing" eliptically (is that a word?) along the surface instead of concentric with the rotation and causing all your noises.

Hard to describe, hopefully you understand,

I'm running 300M rotors on my 1G.
They require a centering ring (on the hub), and the control arms have to be flattened at the outside edge (where the ball joint is).
If Nick did the install, I'm sure that's all been covered.

Even with the control arms flattened, there's been a groove cut into my rotors from the interference.
I would someday like to get new control arms and space the caliper and rotor off a touch more from the hub.

I know Sue is using centreing rings on the rotors, as I made them. Having said that, I made them to the sizes I was given. Sue, can you ask your mechanc how they fit. I think Mike is suggesting your rotors might be "orbiting" indicating the spacer rings are too "loose". Can you ask your mechanic about this? Or did he possibly even forget to install the rings??

I'm actually talking about the brackets themselves. The brackets must keep the caliper "orbiting" around the rotor concentrically to the rotation of the rotor. If not they'll be scrubbing the surface as it goes up and down. Thus causing your noise.

Meaning the original 2 bolt holes, if were to be drawn as a bolt circle in relation to the center of the hub. The 2 NEW holes need to be also be drawn concentric to the original bolt circle.

The purpose of the rings to for just ease of assembly because if your talented enough to position the rotor perfectly centered of the hub ring while torquing down the wheel then you really don't need them. But if the ring is sitting in there sloppy then that could be it also. as the reverse of what i'm talking about is happening.

I've got Ziggy's location rings on my car using cobra brakes and they fit fine. Don't know about the 300M.

I know I was given a set of sizes for the 300M rotors, and they were different than the cobra rotors....hope they are not the problem.

I think sue is using Nick's brackets, and I believe he has the same ones on his own car, so I don't seem them being the issue..

Sorry for the really, really slow response gents. Haven't had time to check the board recently. The mechanic definately checked the fitting of the rings and it's on firmly so that's not the issue.
The funny thing is only one side makes noise now.
The ideal solution will be to go with a floating rotor set up.
I'll just have to see how difficult and expensive this will be to do.