Brake Discs Hairline Cracks on Big Reds..... - Page 3 - Porsche General - PistonHeads UK

??? ??? Manufacturing fault? I'd try the - "so....are discs supposed to last only 8K? These haven't. Can't have been manufactured properly then could they? I know they're consumable but that short a service life isn't acceptable!" etc etc We had discs replaced on our Chim. Under twelve months later they had warped. Replaced under warranty (!) by Hawthorns. Good chaps. Are they telling you that you'll have to pay, Daz? Edited to say: Never had disc problems on any of the Porsches I've owned. Two Boxsters and one old 911. >> Edited by Don on Wednesday 2nd April 14:18

I think they expected me to say get on with fitting new ones. I've told them I'm pretty fcuking far from happy, so they are taking digital photos and sending them to Porsche GB to comment. I will be collecting the car later today, hopefully Porsche GB will be agreeing to do the work under warranty. However this ends up you can be sure I will be voicing my concerns so that all within 20 miles are clear on my thoughts. regards DAZ

Daz, Clubsport(Paul) is the man to ask........he posted on the Ferrari forum,saying that he has experienced this many times on Porkers after track day use.Can be prevented by clearing the holes out after a track run according to his mechanic.Not going to help much on this occassion but maybe in the future. I not saying you shouldn't try and claim through Porsche GB though! Steve >> Edited by sb930turbo (moderator) on Wednesday 2nd April 16:01

Er, I think you will find this is pretty common on drilled disks + performance Porsche + trackdays. You dont have to do 7000 miles for it, just a few hundred hard braking track miles. When cracks get to 10mm I'd replace,ie before they join up the holes ... you just need to think about the disks being a consumable just like pads and tyres if you are doing tracks. I never had it with a 'cooking' 993 Carrera 2 or 996 Carrera 2, but do get it with 964RS. Even if you get Porsche to pay for a new set it is likely to happen again...maybe others can comment ?

Worth going for the carbons, Daz?

Scottster recently got some dosh out of PCGB, where there was a genuine manufacturing fault (old 993 wiring harness having shite insulation that caused a hazardous short). It took him two attempts (the gave him the big bugger off the first time around) and he had to be a little forceful, but they eventually played ball. Problem will be whether they were 'fit for purpose' - I'd say that 8k miles is low, but 250 track miles is more than some people do on the track in a year (I know your laps were bigger ). I am on your side, but they may play the old 'road car' argument. I would go for an upgrade to ceramics and ask them to cover a large proportion of the cost, otherwise you'll get the digi camera out and start snapping on behalf of What Car? ATB Dom

I've heard the same as oldtimer, the cracks are common on drilled discs, but not a problem until they meet. Perhaps 9M could give a more informed opinion? As for ceramic discs, I've heard from 3 different sources (all GT2 owners at Oulton Park on the 22/03) that they are not all they are cracked up to be. Lack of feel and fade can occur particularly when they get hot.

Hi Guys. Just collected the car. I have voiced my opinion to the garage and then The importers, who are investigating "the problem", I'll let you know how it pans out. DAZ (PS - Any guesses on costs of two front discs and pads for a 996tt?)

Don't worry. Mortgage rates are at an all time low

Daz Common problem, I've had the holes join up and bits fly off!, I use solid discs for racing because of this problem (trouble is these warp, new set every 300 miles). Porsche discs are the best (unless you start talking AP Racing etc), so slow down (yeh, right!!) or don't brake Paul

Paul, the latter option seems more appealling. cheers DAZ

About £500? Steve

Are these the rotors with ceramic inserts/sintered pads, or something else? Tarox were making some pretty impressive claims for these at the Autosports show, but I don't know anyone who's actually tried them. Have you?

PCCB Porsche Ceramic Composite Brakes About a 5500 quid option on the 996 Turbo and C4S i think, and standard on the 996 GT2. Special ceramic composite disks with appropriate pads, they reckon these disks will last 100,000+ miles and supposedly don't suffer fade because their overheat temperature is about 3 times higher than normal disks and pads. Believe what you will. VS

Ceramic discs are discs made out of Ceramic. They're a VERY expensive option (7K I think) on the 996TT, GT2 and the new GT3. They're supposed to give improved performance and last the life of the car. Verysideways beat me to it! >> Edited by Paulc on Wednesday 2nd April 21:00

PCCB - I am aware of them. Indeed when ordering the car I tried getting them, but due to a shortage of supply slowing down the GT2 production line, Porsche wouldn't let me have them. I am aware of owners of cars with PCCB who seriously drive their cars and they are pretty bloody far from impressed with them. Opinions seem to be they may be the technology of the future but they haven't got them right yet. DAZ

"When cracks get to 10mm I'd replace,i.e. before they join up the holes ... you just need to think about the disks being a consumable just like pads and tyres if you are doing tracks." I'd second that -drill the dust out of the holes regularly. Front discs on my old C4 would last about 10,000m including a year of track days -I was perfectly happy with that.... Melv

Sorry Daz, you don't want to hear this but I think that you have very little to complain about. You are driving one of the worlds fastest production cars, it weighs in laden at over 1.6 tonnes, has over 400bhp and has the best brakes that Porsche have ever made, known by them as their 2000bhp brakes. In my opinion new discs every 8000 miles is a small price to pay, even at £500 per set. I have the same brakes on my 993RSR and they are renewed every year, at 2000 miles per year. Surface cracking of any Porsche cross drilled disc is perfectly normal, they are usually caused by rapid heat build up (track days a favourite), but are only recognised as a problem when the cracks go through the disc or join the holes together, at which point they must be replaced. As for the ceramics, yes we can do a set, but Porsche want £4200+VAT each for the disc alone. Call me if you want to order them.

Hi 9M Since hearing the shocking news most people I've spoke to have come up with the same comments as yourself. Along the lines of, do you want to drive like a numpty and the discs last 20k? or occasionally drive like a maniac with the odd Nurburg extravaganza using the car as you intended to when buying it. I think I'm going to go through an awful lot of these things!!!!! I note your comment on ceramics but someone I know of has had problems using them on a frequently trackdayed 996tt. Out of interest what do the likes of Gemballa, Ruf, Techart etc put on their 600/750 bhp monster 911's? or do the customers just ignore the cracked discs and change them as frequently as the tyres? cheers DAZ

Sorry to read about this, Daz but I think the man from Del Monte is probably right about the consumption rate. Could be worse, right? I mean, if you'd bought a Diablo you's be looking at £2-£5k every 4-8000 miles for various clutch related operations - on top of everything else going tits up! What's the physics behind their knackeration, though? Pads I can understand but bleedin' 'arry - if this is happening to the reds bits...better get the Pagid pads cleared pre Silverstone, eh?

Interesting point here DeR. The garage said it was caused by overheating. The importer said this sort of thing is caused by braking from high speeds when the pads are cold. Hmmmmmm, so does it happen when the discs are too hot then? or does it happen when the discs are too cold? Either way I can't tell from what I've been advised so far. Although others advise the problem is to be expected from enthuastically driven cars. What set me off on the warpath was being told the probable costs would run to >£1k. I have calmed down now I know this regular occuring job will cost about >£500 a go. DAZ

One thing's for sure, Daz: when it comes to OPCs they should be known as OPRs where the Rs = Rogerers! Then again, my information is - and correct me if it's innaccurate - that you're not exactly Dame Fanny McBatty in the discipline of brutal brake application? For my own part, I tend to use my brakes as little as possible in accordance with the Jackie Stewart maxims surroundinmg the judicious useage thereof and of course, certainly not at all strenuously until things have warmed up some. (Come to think of it, Daz, don't you generally like to pootle until all the motor's juices are hot before unleashing the full howitzer hit of your firepower on an unsuspecting locale?)

That is something I am meticulous about, which is why I utterly refuted the allegation of abusive braking when the pads were cold, on the telephone yesterday. Still we'll see how it pans out. Either way, whoever is paying, I'll have replacement parts in time for the German countryside scenic tour at the end of May. DAZ

I read what ninemiester (is that how you spell it !!) says but I can't agree that this should happen.The Turbo should be designed with at least 20k usage in the disc's, not 8k, it's a near £100k car!!Had a 996 C2 which was driven HARD & still had the original discs at 30+k so I will Pissed to find out that I may need disc's every 8k on my Turbo (I have just done 7k!!). The brakes are better than the standard car but not THAT much better.Daz. if I were you I wouldn't be paying for a new set of pads at only 8K

Sorry to hear about this Daz....hope you get it sorted soon. Fingers crossed Porsche GB will come up trumps. BTW, were you honest with the track action? I mean, what if you lived in the middle of Dokicshire or something, you'd be pulling down from high speed every bloomin' day (my missus certainly does in her car, never a working day goes by without a bit of hoonery with a Scoob or blue BMW 540i)

Grant, I'll have a look at your discs on saturday. If it weren't for the cracking mine are barely grooved and 20k miles could be be done easily on one set of discs. Have you done any trackwork? Greg. Honest!! Moi? Yes of course, 250 miles of tracktype activity made up of 17 laps touring the Eiffel countryside in Septmeber and half a dozen blasts down a runway in March (I have excluded my 7 laps in May as it was wet and I was literally pootling along without the need for brakes). regards DAZ

Update. Porsche have confirmed to me the cracks are normal for a car that is driven hard. The discs are servicable upto the time the cracks get to 7mm and over. They deny it is a warranty issue but confirm that if the hairline cracks do get to 7mm they will look again at the mileage covered etc with a view to possibly making a goodwill gesture. DAZ

Hi Daz, Take it you are not forking out for new ones yet then?Its no surprise to me the response you got from Porsche UK,in view of the views others have expressed! Steve

Daz; completely off topic: does your car have a sports exhaust? Sorry if that's a bit "next contestant, Cybil Fawlty, specialised subject - the bleedin' obvious" but I canna recall... Anyway, back on topic: do OPCs check such things at service time? Wierd.

Hi Steve I won't be buying discs until after Bruntingthorpe on the 27th. When new rear tyres will also be going on. If I'd known Porsches weren't supposed to be driven hard I might have bought a dancing donkey instead.....Nah, that's getting silly, Donkeys couldn't do what I must have alledgely done to have buggered up the front discs. cheers DAZ (still smiling)

My exhaust is the standard unit you get with the X50 power upgrade. Manu say's it louder than the standard turbo exhausts he'd heard but I've never compared. Besides it's nothing like the MMMMMAAAAADDDDD stuff he fits to cars. I have neighbours to consider. During the first service the mechanic did check the brakes and brought the problem to my attention. I don't know if they check for non standard components such as exhausts (not sure what bit you were querying). DAZ

OK Daz, so how big/long are your cracks then ? I assume they are on front disks only . Once you've got them, they just grow a little bit per trackday, normal road stuff does not seem to grow them. On a track like Oulton, a 2 min lap will involve say 6 lots of heavy braking from 120mph (+) down to 50 in 100 metres or less...so heat just builds up in a 20 min session, specially if you are pacing the 500kg Caterham efforts and you ( 911TT) weigh in at closer to 1500kg...you are pushing the brakes hard and they become a consumable ...at least you are not in the full racing mode where engines become a consumable too !!

Hi Oldtimer. Front discs only the cracks are about 3mm. Porsche have said the discs are servicable upto 7mm. You mention trackdays braking from 120. Unfortunately my idea of a track day is doing 175mph runway blasts or 2 days thrashing around one of the more scenic areas of German countryside in 9 minutes give or take traffic on the toll road. Hence the problem I'm beginning to think. cheers DAZ Edited to say I'd like to do UK trackdays but I can't fit in my car wearing a helmet. >> Edited by dazren (moderator) on Thursday 3rd April 21:43

Update. Following advice from a fellow 996tt owner on another forum I am investigating getting GT2 airflow scoops to divert more air onto the front discs. The OPC are getting me a quote and investigating with Porsche GB if it is OK to both fit them and remove the brake dust shields which would hinder the additional airflow should they be installed. DAZ

Daz,,, interesting but personally I wouldn't spend the money as I don't think it will make much difference. The reason I say this is that I have seen guys on trackdays with 993 GT2 who basically run the same big red set up as you,,they still get the cracking with air ducting as the brakes get V.hot. I feel it goes with the territory,I bet this fancy ducting lark costs more than a set of discs/pads anyhow. I would get original equipmwnt discs/pads from a specialist when you need them & save a few quid.There is another alternative,you could get a Boxster they are lighter and don't generate the heat so much..and you could wear a helmet in one for trackdays... Don't see this happening somehow?

The GT2 airscoops are just bits of plastic that is attached to the wishbone. Let's see how much they quote first before righting off the idea. The person who recommended them has run both standard and ceramics on his turbo and has these scoops fitted (And yes he enjoys regularly touring the german countryside in less than 9 minutes) Good idea about using independents for replacement of OE discs and pads. Although there isn't anyone local to me I've asked the OPC to give me a quote first, so I can make a few phone calls and compare. cheers DAZ

This makes me wonder what the hell we were doing at Le Mans in '52 and '53 with our 'final' testing of discs - OK, the speeds were lower (150), but the weight was one tonne plus 40 gallons of fuel. No chicanes on the Mulsanne straight, but six full-on braking zones every lap for 24 hours. So what are the 911s using at Le Mans (with the chicanes) nowadays? Will find out if no-one knows. Probably a set-up totally unsuited to road use, but they'll still stop the thing given a bit of leg muscle. Nothing more boring than old memories, but if it's any comfort there's always been a down side - my gullwing used up a set of drums exactly when the tyres went bald - at 2,000 miles....

Daz,a very nice guy in our group who was into his cars,yet did not have petrol in his veins if you know what I mean,arrived in his 996 GT2,well his 996TT was at home. I remarked that he had regular steel disc brakes on his GT2.I was told that it took too long for the ceramic brakes to get heat into them for road use. The petrol/veins thing was only because owning these he wasn't interested in track days...top man though!

McNab - I'd be interested to hear that but I can just imagine the conversation with my insurers. "Hello, this is Mr Dazren, policy......, I'd just like to notify you of an update to my car.....due to an alledged abusive driving style I've had to put Lemans standard brakes onto my road car........I trust this will not result in an increase in premium" Sounds of a hysterics in the background, phone goes dead........ 10 minutes later, phone call from credit card company advising I've exceeded my limit by £10k. As for the drums and tyres on the gullwing, respect is due sir. :donscap: Paul - the guy with the ceramics swapped back to steels probably had the same problem as the turbo owner I've mentioned earlier who has had problems with ceramics. Then decided to go the "reliable route". That is reliable unless your name is Dazren or you are the other PHer I met on saturday who obviously drives his car properly. DAZ

Daz, Not sure if your discs are the same as the 993TT but if they are i can give you an idea. I buy my genuine Porsche discs from Euro Car Parts for 290 quid inc VAT. That's fronts for the 993 C4S, RS, TT and GT2. Obviously you have to buy new pads as well, but i fitted my new discs and pads in less than 2 hours and that was going slooow. HTH VS

Daz No, no, no - I wasn't suggesting that! It simply struck me that because such an extreme technology exists there must be a half-way-house. Porsche are well aware that hundred's of 996s are raced all over the world in less serious events, and hundreds more used for track days. Strange if they haven't catered for this. There must be something that works for these guys and, if the price is half-way reasonable, a club racers' disc with softer pads would be useful. My point about the development was that we seem to have spent 50 years going from the simple to the totally unaffordable - wish you good luck finding a cure! Ian.

Daz, who might that other PHer have been? Regards discs my dealer is currently investigating the TAROX ceramic/metal discs in the hope of achieveing the best of both worlds, having suffered the same problem, will let you know what I learn.

Oops. Should have made that two other PHers who drive their cars "properly". I was referring to another Porker owner. But I would just like to give credit where it is due Charlie, you too are a member of the PH Brake Disk Destroying Elite. DAZ

Of course you could also consider AP discs! I know that AP will make a disc-bell to suit the original calliper, and then you would buy "grooved" AP discs, which should last twice as long! I think the cost for the bell is around £350 per corner. A mate has an M5 (1800kg) that he tracks quite a lot and drives very hard on the road, he runs AP 6 pots with grooved discs and Pagid RS19 (yellow), amazing stopping power, and unbelievable longevity! I can put you in contact with a friend of mine who runs a successful motor sport company (being careful not to advertise - won the British GTO championship in their first year – so know their stuff) I am sure he can help you out! If you want contact details let me know – must worth a phone call at least!

I think the simple truth is that any car used 'properly' with cross-drilled disks will eventually get cracks between the holes, which leads to premature replacement. The only alternative is non drilled disks, or grooves. The holes are only there to allow water to escape or help prevent the pads from glazing (or to look fancy ). If it's wet you will not be going as fast, and if the pads glaze then they are much cheaper to replace.

Mark H. Thanks for the idea, for now I'll wait to see what answer I get about the GT2 airscoops. For now I'd like to try and keep the car as standard as possible for insurance purposes. cheers DAZ

Has anyone had experience of these with porkers. I've just had a call from the garage telling me the front discs on my car have "hairline cracks" which are probably caused by overheating. Saying as the car only has 8k miles on, of which 7750 were road miles and 250 under "track dawdling" conditions I'm a little concerned about the quality of the brake discs used. I'm even more surprised as I've never even experienced brake fade with the car, so how the hell is the problem caused by overheating. DAZ