JulesB

How are folks finding HiSpec brakes?
I had mine fitted in January:
Monster4 calipers (black with "HI-SPEC" on)
305 grooved discs on gold bells (Standard 16" wheels)
Ferrodo DS2500 pads
Goodridge hoses all round
Silkolene pro-race fluid.

They have been excellent on the road even though I have had some loud squeeling after heavy use, but then I went to Knockhill...

Braking was generally excellent. Hitting the middle peddle just after "Brake" signs, no ABS, no fading just a loud moaning noise which decreases in pitch as you slow (I think this is pretty common for all brakes... or maybe not)

BUT...after a few outings (only doing 5-6 laps at a time) I noticed a chattering noise while entering the pits, which stops the moment you touch the brakes.
The noise hasn't gone away and pedestians are starting to stare (it might just be the gorgeous car or even the driver... but I doubt it)
Took it into my local dealer (who fitted the brakes initially) who stripped the brakes, cleaned, copper greased etc, but the noise is still there. They recon the noise is simply the pads rattling up and down in the caliper.
The mechanic noticed that the discs had been rubbing on the back edge of the calipers and that the two pins behind the pads also had rub marks on them, there is also some swarf visible on the leading edge of the caliper where the face of the disc rotates.
He thought that this damage must have occured when the discs where very hot but was surprised that they could expand so much.

So to questions:
1) Is the loud maoning noise common on most brakes?

2) Any one else getting this chattering noise on Hi-Spec brakes after track use? Has anyone managed to cure it? Maybe its specific to Ferrodo pads.

3) Can the discs expand the 3-4mm needed to rub on the calipers, or could somthing flex that much to allow the disc to reach the caliper?

Finally, I believe that Hi-Spec are trying to design a shim/clip thingey that will hold the pads better to stop any movement. I'm not sure when this will be available, but at least they are trying.

GavinP

Is the "moaning" noise not the grooves in the disk ?

R 5C0DBY

i do get a chattering with mine altho i got the high spec conversion its with wilwood calipers! as for the moanin mine does also just the grooves!

Fizz

iTrader: (1)

Mine do the same. They make a knocking noise when they are warm. The pads rattle around quite a lot in the calipers. Mustbe the grooves moving the pads.

JulesB

Thanks for the bits of reassurance.
If Hi-Spec sort the rattling problem like they say they will then I'll post the solution.

Matt Churchill

Just a thought, havce you still got a spring clip holding the pads in place within the calipers?

If not, it could well be the pads moving around within the calipers and making a noise when you go over bumps etc and "shake" them.

Fizz

iTrader: (1)

there are no springs in the hi-spec kit to hold the pads in on mine. hi-spec fitted mine too!