991.1 Turbo S purchase advice

[jabbathut]

Hi all,
I am a new member so apologies upfront if I am posting this in the wrong place. Here goes...

I am looking to purchase a used 991.1 Turbo S from a reputable, independent Porsche specialist I purchased my current car from. Having agreed a price, the car underwent the detailed pre-sale inspection and they found a score mark on one of of the carbon brake discs. They were open and honest about this discovery and have said they will not sell the car with this disc in situ for safety reasons. However, these things are not cheap to replace and the current owner of the vehicle has said they will pay for the brakes to be changed to steel discs all round, but will not stretch to a replacement pair of carbon discs for the front.

My concern is that when I come to resell the car, the value will be seriously impacted by the fact it does not have the PCCBs, as they are standard equipment on a Turbo S and any potential purchaser would expect the car to have them. The Porsche specialist is suggesting there would be no real impact on the cars value, which in short, I am not entirely sure I believe. I was hoping to get some independent opinions from this forum on the re-salability point if possible.

Background
I currently drive a modified 997 turbo that had PCCBs specified as an option and swapped them for GiroDiscs pretty early on with a plan of putting the PCCBs on when I sell the car. I know that there is pretty much no noticeable difference in braking performance and am aware of the cost of replacing the PCCBs so I get the real world benefit of not having PCCBs. That said, I won't be tracking the new 991 and plan to do light mileage (c.2k a year), so I think it would be a very low risk of having to replace the PCCBs during the time I have the car.

Thanks for the help in advance.

 

[ralphmusic]

I would be concerned at it having iron discs, presumably the owner/seller would keep the rear PCCBs and sell those? I can't imagine a subsequent buyer wouldn't have diminished interest.

Try https://teile.com/en/porsche-tequipment-shop/model-911-991/27/Performance/PCCB-ceramic-disc-brake/222 for pricing on used discs. Problem is that they are not always available.

Iron discs have different callipers so not just discs. I looked at a 991.1 GT3 with PCCBs and the all in cost of changing to iron was £7.3k. The cost of new front PCCB discs + pads is £10k (plus odds and sods and labour).

I'd ask for the alternate costings as above and negotiate.

 

[Lancerlot]

Interesting question.

We are assuming the current rotor is scored beyond being reclaimed.


I don't think there will be a big market for a Turbo S on iron brakes.

If the current owner is willing to stump up for a brand new iron set all round, he's probably not far off the cost of replacement front carbon rotors since, as Ralph says, using Porsche approved parts callipers, hubs, pads etc must all be replaced too. However I suspect he may be thinking of swapping out for a used set off a scrapper somewhere or something.

Personally, I would walk away. It's not worth all the agro.

Regards,

Clive

 

[jabbathut]

Hi Ralph, thanks for the speedy response and for your opinion.

When I spoke to the dealer about changing the discs they did not mention anything about changing the calipers (the price they quoted for the Giros was c. £4k fitted) and as an aside, when I had my 997 converted I did not have to change the calipers either, but I will make sure to ask next time I speak to them.

This may be a silly question but I notice on the site you linked above that they sell new, individual discs. I presume it would be a bad/terrible idea to just change one of them?

 

[jabbathut]

Hi Clive,
thanks for your input as well. I have to say I am starting to agree with you and am leaning towards walking away.

Shame really as I really liked the car :-(

 

[ralphmusic]

Girodiscs would be direct replacement for ceramics whereas if you were fitting OEM iron disc they are smaller diameter and maybe different offset.

I am sure Clive would concur, change discs, pads in axle sets.

 

[Lancerlot]

Yes, you can't just change one side.

The difference with the Turbo S is the centre locks (I don't believe iron rotors were offered as a factory option on TTS).

The rotors are 2 piece mounted on bells, which in turn mount on PCCB-specific hubs, so a change over is quite a big deal and IMHO not really worthwhile when you also take into account the reduced residual value.

I'd make replacement for a pair of new front rotors part of your deal. You could always add a bit to it yourself to sweeten the pill if you feel there's an element of betterment. But in the end be prepared to look elsewhere!

Regards.


Clive

 

[jabbathut]

Final update on this,

I have just got off the phone with the dealer and the seller is not prepared to negotiate and has said he will just keep hold of the car for now so way forward seemingly. Just wanted to say thanks again for the help and advice in any case

 

[Lancerlot]

You'll likely look back later on and heave a sigh of relief it didn't come off.

Regards,

Clive

 

[Shortshift]

I recognise that you are planning to walk away but, maybe as a final check, I'd ask for a detailed description (or maybe a photo) of the alleged markings to the disc. The Porsche standards for what is and is not allowable are easy to find online. The dealer should not assume, simply because there is some minor marking, that the disc needs to be replaced.

You never know, the disc might be well within the Porsche standard for service and resale, in which case you might be well placed to leverage a better deal on the car without there being any real reason for concern. On the other hand, of course, it could be that the marking is well outside of the allowable limits, but at least you'd know and could walk away with confirmed justification.

James

 

[tscaptain]

There are 55 991 Turbo S for sale on Autotrader currently. I would look elsewhere and avoid the worry, as mentioned previously.

 

[jabbathut]

Interesting update... The dealer has been in contact with Surface Transforms, who I believe are very reputable for aftermarket ceramic disc conversions and they have said there is no issue with running standard PCCBs on the rear and their discs on the front. This brings the cost down considerably to around £1,500 over the cost of a full set of Giros instead of upwards of £6k more using Porsche parts.

The seller has agreed to paying this extra amount but the question still remains around how the replacement is viewed? I am much happier with the ST discs than the Giros and by all accounts the ST discs actually out-perform the standard PCCBs...

 

[Dylan1]

When you come to sell it I suspect any saving over standard car will be reflected in the price you get at resale
if you’re not going to sell for several years it may we’ll be worth it to you to go for it

 

[Nordschleifer]

In case it helps..

A scored PCCB indicates the ceramic surface coat is breaking down and will soon fail catastrophically. To be sure on PCCBs, all you have to do is measure them with the Carbotech laser device. All specialist/dealers should have them. Never ever buy a PCCB car without this check.

My knowledge on this subject comes from running my own PCCB equipped car on the Nordschleife, and lots of extremely helpful & honest conversations with race engineers at Manthey. I had them checked every day with the carbotech to make sure they were within spec. It's astonishing how many folks never check them with the device and track the car with no idea they are dangerously below minimum density. It is then that the surface starts to fail and score, or worse, chunks fall out. I've not met a tech at an OPC in the UK who even knows they have the device in the workshop.

I've cooked my PCCBs now, but having experienced carbon ceramic brakes, I will never ever use steels again. However, rather than pay for new PCCBs I am upgrading to Surface Transform discs. If you can take the initial 10 grand hit, they work out considerably cheaper than steels over their lifetime (>20,000 track kilometers). And perform better than steel or PCCB into the bargain. And weigh less than both too. Go figure... (I guess that's why they are OEM on Singer

A PCCB equipped car used only on the road should never get anywhere close to surface breakdown in the lifetime of the car. They should never need to be replaced anyway.

You have to REALLY heat them up to burn off the carbon fibres themselves (and thereby reduce their density, and the effect this has on disc integrity & performance).