What do worn ceramics looks like?

[DanH]

Should they be perfectly smooth? I looked at a car yesterday, and the discs looked slightly pitted along the edges of some of the 'fibres' its composed of. Not sure if that is normal or the first stage of an incoming bill?

To be fair it looked fairly consistent like this across the discs so I'm guessing it may be normal.

Also anyone know the deal about RS PUs and bonnets yellowing? Been told the bonnets don't yellow now, but the PUs do.

Oh and also the front air intake modification - anyone know what that is.

[BobM]

DanH said:

Should they be perfectly smooth? I looked at a car yesterday, and the discs looked slightly pitted along the edges of some of the 'fibres' its composed of. Not sure if that is normal or the first stage of an incoming bill?

I think that's normal. They don't 'wear' as such but develop cracks when they're getting tired.

Has the car been tracked? My experience of OPCs has been that they've been honest when asked. If not then I wouldn't worry. If it has then budget a couple of £K for steel replacements?

[Paul Y]

DanH said:

Should they be perfectly smooth? I looked at a car yesterday, and the discs looked slightly pitted along the edges of some of the 'fibres' its composed of. Not sure if that is normal or the first stage of an incoming bill? To be fair it looked fairly consistent like this across the discs so I'm guessing it may be normal. Also anyone know the deal about RS PUs and bonnets yellowing? Been told the bonnets don't yellow now, but the PUs do. Oh and also the front air intake modification - anyone know what that is.

Having had my ceramics replaced I can tell you what they look like first hand.

The disks when new are a dull grey colour which very rapidly changes to an uneven colouration across the disk.

The disks then start to "pit" like a bad case of achne, still perfectly servicable.

Then they delaminate.

The strange thing is that the brakes worked at their best just before I had them changed!?!

Took 11K miles to go from dull gray to in the bin.

Price to change them to steel is about £1K for the fronts if you go the Alcan/Bembo route which would then reduce the ongoing disk cost as you only replace the rotor not the hat.

I have been told that the reason the bonnets and PU yellow is to do with the release agent used in the molds. Could be a load of old bolax as not all of them suffer. Good thing is Porsche will respray the front end under warranty, good way of getting rid of the usual stone chips etc at the end of the year.

The front air intake modification deflects the air from under the car and through the vents along the leading edge of the bonnet. Supposed to be good for more front end downforce at 125+. Had it done on mine, bit difficult to tell if there is a differance. Having said that at a big speed on the way to Le Mans last year the car was incredbily stable and there was a point when I could feel the aerodynamics coming into play. The car got "heavy" if that describes the feeling.