Discussion
Coincidentally I've just bought a 350mm front * and 325mm rear set of GiroDiscs directly from Girodisc and a GT3 brake master cylinder for my 981 Cayman S. I also have DS1.11 pads to install with the GiroDiscs.
There are two versions of brake master cylinders fitted to 981/991 models (cooking and GT). In early 2014, Porsche moved the brake light activation from the brake pedal to the master cylinder. The VIN # is the best way to ensure the correct part is identified.
Anyway master cylinder on first see what difference it makes, then install discs and pads.
My reason for moving to GiroDisk slotted discs was because I was fed up cleaning out the drilled holes after each track day. My discs did not crack much due to this maintenance regime.
There are two versions of brake master cylinders fitted to 981/991 models (cooking and GT). In early 2014, Porsche moved the brake light activation from the brake pedal to the master cylinder. The VIN # is the best way to ensure the correct part is identified.
Anyway master cylinder on first see what difference it makes, then install discs and pads.
My reason for moving to GiroDisk slotted discs was because I was fed up cleaning out the drilled holes after each track day. My discs did not crack much due to this maintenance regime.
- I have 991.1 6 piston front callipers
Rocket. said:
Very interested to hear how you get on with the new front Gyrodiscs 911r. Have been thinking about doing the same on my CS as on track it's lacking with all the upgrades you have mentioned, bigger disks should make a difference I am sure, after all people fit Porsche 986/996 front 4 pots to E46 M3s which weigh at least 10pct more than our cars but with a bigger front disc they apparently work fine.
I have also made some ducts for the rear brakes using those from a 997 turbo with a bit added to get them more into the airflow.
I'll post my review as normal, they have to be better, it's just by how much, I don't have the GT3 MC as I don't like that mod , I do have GT3 ducts though.I have also made some ducts for the rear brakes using those from a 997 turbo with a bit added to get them more into the airflow.
I could be tempted to fit the PCCB MC from the Cayman S if the travel is too much but I dislike the limited travel the GT3 one offers.
The Cayman PCCB one which is in my 987 Spyder is a half way house, but people fit the MC because of long travel and longer travel only happens with heat this setup might cure that.
gtsralph said:
Coincidentally I've just bought a 350mm front * and 325mm rear set of GiroDiscs directly from Girodisc and a GT3 brake master cylinder for my 981 Cayman S. I also have DS1.11 pads to install with the GiroDiscs.
There are two versions of brake master cylinders fitted to 981/991 models (cooking and GT). In early 2014, Porsche moved the brake light activation from the brake pedal to the master cylinder. The VIN # is the best way to ensure the correct part is identified.
Anyway master cylinder on first see what difference it makes, then install discs and pads.
My reason for moving to GiroDisk slotted discs was because I was fed up cleaning out the drilled holes after each track day. My discs did not crack much due to this maintenance regime.
Do you have a travel issue then ?There are two versions of brake master cylinders fitted to 981/991 models (cooking and GT). In early 2014, Porsche moved the brake light activation from the brake pedal to the master cylinder. The VIN # is the best way to ensure the correct part is identified.
Anyway master cylinder on first see what difference it makes, then install discs and pads.
My reason for moving to GiroDisk slotted discs was because I was fed up cleaning out the drilled holes after each track day. My discs did not crack much due to this maintenance regime.
- I have 991.1 6 piston front callipers
with the ds1.11 pad which is aggressive I would do the brakes 1st then only do the MC if you want less travel.
the 981 Spyder has the 911 set up with 350MM disks and it's an aggressive set up, there is no way on earth I would want less travel on that car.
Porsche911R said:
Do you have a travel issue then ?
Just looking to improve brake feel which of course is an individual thingPorsche911R said:
with the ds1.11 pad which is aggressive I would do the brakes 1st then only do the MC if you want less travel.
For me personally it is not all about travelPorsche911R said:
the 981 Spyder has the 911 set up with 350MM disks and it's an aggressive set up, there is no way on earth I would want less travel on that car.
I thought the Spyder had 991.1S front callipers and 340mm discs?gtsralph said:
Porsche911R said:
Do you have a travel issue then ?
Just looking to improve brake feel which of course is an individual thingPorsche911R said:
with the ds1.11 pad which is aggressive I would do the brakes 1st then only do the MC if you want less travel.
For me personally it is not all about travelPorsche911R said:
the 981 Spyder has the 911 set up with 350MM disks and it's an aggressive set up, there is no way on earth I would want less travel on that car.
I thought the Spyder had 991.1S front callipers and 340mm discs?I find modulation of a brake pedal is easier with more travel ,other disagree, but it's basic maths. the 981 has more servo aids so travel is already short imo hence there is no way I would want a shorter pedal on the 981 Spyder, be like a on/off switch.
The DS1.11 pad should give you more feel and bite.
brake size, my mistake 340mm front 330mm rears , it's hard to find the info on rarer cars as no one lists parts sizes. I thought it was a 350MM set up like my 987.2 Spyder disks, but that uses 996 GT3 calipers !! they do move parts about a lot between cars !
Edited by Porsche911R on Tuesday 13th February 14:40
Porsche911R said:
brake size, my mistake 340mm front 330mm rears , it's hard to find the info on rarer cars as no one lists parts sizes. I thought it was a 350MM set up like my 987.2 Spyder disks, but that uses 996 GT3 calipers !! they do move parts about a lot between cars !
If I recall your 987.2 Spyder has PCCB which are 350mm and I think uses the same callipers as 981 and 718 series PCCB.Edited by Porsche911R on Tuesday 13th February 14:40
I have essentially the same callipers as the 981 Spyder so my rear upgrade is to 325mm from 299mm stock. I did think of fitting the PCCB calliper to get 350mm all round but I was not convinced the cost of new callipers (and painting front or rear to match) was worth it - we shall see.
The trouble I find is that most UK Porsche Centres' parts and technical staff don't have access to information beyond the PET files. I find out more talking with USA shops and Rennlisters who actually fit non-standard parts and have gone through the "will it fit" experimentation stage.
Twinfan said:
Do you have the part numbers for the rear brakes?
Most PET files (covering all geographic markets) are available on the Porsche USA sitehttps://www.porsche.com/usa/accessoriesandservices...
Twinfan said:
...did you have to mess with the brake bias settings in the ECU?
I am not sure about messing, the option is binary; iron brakes or PCCB settings. There is a school of thought that any rear change should be accompanied by using PIWIS to set the ECU for PCCB which are 350/350mm. In my case I will have gone from Stock 330mm/299mm via 340mm/299mm to NOW 350/325mm so overall proportionally from 1.10 : 1.00 to 1:08 : 1.00. Setting aside my earlier front calliper change from 4 piston to 6, neither the disc size nor reported USA experience suggests an immediate need to change ECU brake settings.My Cayman R had a cable snap on the gear box...Not sure on the technical terms but was covered under warranty so that's being sorted.
It's due a service and few other bits have popped up on the health check. The service itself with brake fluid, drive belt, tyre pressure battery its totaling over £700 along with brake pads and drilling of discs over £500 and some corrosion on the exhaust where the flange fixes on which is labor intensive at over £500.
Quite a big hit that I wasn't expecting just yet - are these prices worth it? I'm looking at renewing my porsche assist given how good it was for me, do I need to be using OEM parts to keep it?
It's due a service and few other bits have popped up on the health check. The service itself with brake fluid, drive belt, tyre pressure battery its totaling over £700 along with brake pads and drilling of discs over £500 and some corrosion on the exhaust where the flange fixes on which is labor intensive at over £500.
Quite a big hit that I wasn't expecting just yet - are these prices worth it? I'm looking at renewing my porsche assist given how good it was for me, do I need to be using OEM parts to keep it?
Edited by lukeyboyuk on Wednesday 14th February 09:53
lukeyboyuk said:
My Cayman R had a cable snap on the gear box...Not sure on the technical terms but was covered under warranty so that's being sorted.
It's due a service and few other bits have popped up on the health check. The service itself with brake fluid, drive belt, tyre pressure battery its totaling over £700 along with brake pads and drilling of discs over £500 and some corrosion on the exhaust where the flange fixes on which is labor intensive at over £500.
Quite a big hit that I wasn't expecting just yet - are these prices worth it? I'm looking at renewing my porsche assist given how good it was for me, do I need to be using OEM parts to keep it?
A fixed price service is £415 belts are £163, fluid is £95 , the AA is £75.It's due a service and few other bits have popped up on the health check. The service itself with brake fluid, drive belt, tyre pressure battery its totaling over £700 along with brake pads and drilling of discs over £500 and some corrosion on the exhaust where the flange fixes on which is labor intensive at over £500.
Quite a big hit that I wasn't expecting just yet - are these prices worth it? I'm looking at renewing my porsche assist given how good it was for me, do I need to be using OEM parts to keep it?
why does a disk need drilling ? they love the flange thing atm OPC must have had a mail out on it to make money !
Porsche911R said:
A fixed price service is £415 belts are £163, fluid is £95 , the AA is £75.
why does a disk need drilling ? they love the flange thing atm OPC must have had a mail out on it to make money !
OK mostly sounds reasonable pricing then. The drilling I don't actually know exactly, I assume because the current holes are clogged up. My brake pads are 90% worn so maybe heating is an issue here. I'll have to ask for more info!why does a disk need drilling ? they love the flange thing atm OPC must have had a mail out on it to make money !
edc said:
It's easy enough to poke a drill bit through the holes to clean up the disc holes yourself. Almost therapeutic but it does take more time than you might realise.
I use the hose. You could use an air gun.I'd estimate 100 holes on a front disc. Who wants to take a punt on their number?
ATM said:
I use the hose. You could use an air gun.
Even though the pads are asbestos free, i wouldn't use an airline unless you've got some decent eye and breathing protection. 
Using a hose/jetwash does work, but doesn't clean them out as well as a drill bit.
Over time the metal surrounding the drill holes oxidises and even a high pressure hose/jetwash won't shift that oxidised material.To do the job properly, they're best drilled out. in my experience.
edc said:
You need some decent pressure to use a hose to budge the compacted crud and then it's in your face bad makes a huge mess. A drill bit is just more accurate and cleaner. Just like it through and then use it like a file around the circumference of the hole.
Beter stll, use one of these (gently) and note the speed recommendations ...https://www.shop-apt.co.uk/carbide-burrs-90-counte...
Mogsmex said:
any chance of the link for the tips, they look lovely and although I have buffed mine as much as possible there not cutting it
Cheers
I got them direct from the USA and Fabspeed, the disks were so much cheaper even with all the duty and post, so I added tips at the last minute, I was going to just get mine replated for about £150 but the black chrome goes well with the Cayman R looks and I thought sod it lets have new ones.Cheers
https://www.fabspeed.com/porsche-987-2-boxster-cay...
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