temporarychicken Posted August 31, 2016 Report Share Posted August 31, 2016 Everybody knows that the standard brake systems fitted to Porsche cars are always class-leading, and usually superior to vehicles from the competition! This is very true, and all Boxsters have at least four-piston solid Brembo Calipers all-round. The disc sizes are not usually enormous when compared to Audi, BMW sporting models, but the calipers are light years ahead. My other car, a TT V6 Mk2 with similar BHP and overall weight has bigger discs up front than my Boxster (340mm wheras the Boxster has 315mm). However, the caliper on the TT is a sliding system with a single piston - cheaper and inferior. Also on the TT, the calliper is aluminium but the frame that holds it to the hub is steel. Another difference is the Boxster has drilled discs and brake air-scoops fitted to the front suspension arm. If you look at the brakes on both cars through the wheels you would see the bigger caliper and bigger brake disc of the TT and be fooled into thinking that it could out-brake the TT. It's a similar situation with the old E92 BMW M3 which had enormous brakes but a reputation for issues under heavy use. So even the 981 Boxster base has excellent brakes for the road. On the track the standard factory-fitted Porsche pads will wear away extremely quickly due to overheating. @Buzzfox has also suffered this issue. Not only do the pads wear away exceptionally quickly, but the discs overheat causing small cracks radiating away from the cross-drilled holes. The weakest link on the track of the 981 is the brakes. It doesn't matter whether you have a Base model or a GTS - same issue! For this reason I decided to try and improve on the brakes a little bit. The improvements I have gone for are: 1. Uprated front brake cooling ducts 2. EBC discs (front) 3. EBC Yellowstuff (front and rear) 4. Motul RBF 600 brake fluid First off, is stage 1 - replace the brake cooling ducts. The standard items, pictured below, are actually pretty good, and would be considred an upgrade for previous generations of Boxster. These ducts are fitted to all 981 models and the non-S versions of the 911. The upgrade part (on the right below) comes from the 911 3.8 models (991) and is a straight swap. There's a subtle difference but hopefully enough to guide substantially more air into the central vent of the brake discs: Fitment of the new brake cooling ducts requires either separating the track-control arm from the hub, or undoing the track-rod end from the steering rack. I chose this option. If you do too, be careful not to mess up the tracking setting! The new ducts, now in place (below), look much more purposeful. Let's hope the increase the airflow enough to reduce disc temps during hard use. The next stages (2 and 3) begin with getting the old brake discs off: They are not worn out, but need a skim before re-use, as there is some slight ridging that has formed over three years of use. Also overheating has caused tiny cracks to occur at the edge of the cross-drillings. These should hopefully disappear with a light skim. If a skim does not substantially improve this sutation, then maybe a dustbin job for these original items. The old disc is removed, the hub flange is wire-brushed and copper-eased, and the new EBC yellowstuff pads are installed into the caliper. The pads are simply a push-fit but the pistons in the caliper must be zeroed. This is achieved by pushing the pads back as far as they can go - making sure the level in the brake master cylinder reservior doesn't overflow. EBC provided the new brake discs. These are handed so make sure the cross-drilling patter matches the disc you took off! The discs are superb quality, but are supplied unpainted so you need to add your own high-temperature paint to the hub flange area. This is optional but does look a lot better and inhibits unsightyl corrosion. Once they are all back together it all looks way nicer! The caliper simply has two allen-bolts that hold it onto the hub. There is also a 10mm bolt that needs to be released where the rigid hose meets the flexi - to allow the caliper enough movement away from the disc. Make sure the caliper does not dangle -sit it on something. EBC have designed the brake pad box perfectly for this purpose, albeit inadvertently. According to Porsche these are 'stretch bolts' and should be replaced every time. Also not shown are the wear sensor wiring. These sensors are not integrated to the pads and available separately. The simply clip into the top of the pad and plug into the harness on the hub. At this stage, the fronts are done, and it's time for the rears. I'm not replacing the discs here, just the pads. This is the simplest job in the history of brakes! The rear pads look like this: To replace them, simply pull out the small retaining clip that holds the roll-pin into the caliper with a pair of pliers. With a hammer and suitably sized punch, drive out the roll pin. The spring will then jump off somewhere and you can slip out the old pads. Swap the pads one-at a time. and zero the pistons by pushing with your fingers. Light pressure is all it takes. Once the pads are in, the spring is pushed back into place and the roll-pin re-inserted, together with the retaining clip. You can renew these items too if you wish, but I don't bother if they are in good order. Also renew the sensor wires if necessary. These are push fit. I am not going to do this, however as I am deleting these items for the time being. I prefer to look at the pads through the wheels to get my wear indication! I have made a stub by just joining the wires together at the plug. This satisfies the wear indicator circuit so no warnings inside the car. The final stage, the brake fluid, will have to happen some other time. I don't even have the fluid yet.! It's available from Opie Oils at 25 pounds for 1 litre though. Link to comment Share on other sites More sharing options...
jayk Posted August 31, 2016 Report Share Posted August 31, 2016 Let me know how it goes. I used EBC Turbo Grooved Heat Treated Discs and EBC Yellow Stuff pads on my 950kg track car and I went through front pads every track day, RBF600 boiled too. Switched the pads out to Carbon Lorraine RC6 pads and Castrol SRF fluid and was able to run 40 minute stints no fade little wear. For road I find Yellows need heat before working and on track not good enough or fade to early. Will be interesting to hear you thoughts after some time. Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 In my experience EBC yellowstuff is only really entry-level as far as track-days are concerned, so a rest for the car every 25 min will be prudent! I'm not expecting racing level (continuous) endurance with this setup! The latest compound for yellowstuff has lasted 2.5 track days on another car of mine earlier this year. The road manners on yellowstuff are excellent too nowadays, so as a relatively inexpensive one size fits all pad they are okay at the price. CL are not made in my pad shape but Pagid RS29 are - albeit expensive. The ultimate upgrade for the track on this car would likely be RS29 plus the castrol fluid - as you have already discovered, but we are taking triple the budget of what I've done here and road manners would likely be compromised, esp for winter driving. Thus far I've not even boiled the standard Porsche brake fluid. I think @Buzzfox had had issues with fluid though in his GTS. I have a track day on the 24th so we will see how this upgrade holds up! Link to comment Share on other sites More sharing options...
Tony Daniel Posted September 1, 2016 Report Share Posted September 1, 2016 I've used the red stuff pads before and they have been fine, they have a added advantage of not covering your wheels in dust. For track days I use RS19 pads and RBF600. On the 987 an upgrade is to use the larger master cylinder off a GT3, I don't know if this is feasible on the 981 ? Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 Swapping to serious track pads just before and after the track day is probably the best answer. The holy grail of a pad that's tough enough for the track and well mannered enough for the road is a holy grail! Link to comment Share on other sites More sharing options...
JohnSyn Posted September 1, 2016 Report Share Posted September 1, 2016 Really informative article, thanks for this. I've only tracked mine once so far, another day next week, but have looked at the pads on my car and they don't seem to have worn much. I will look again after the track day next week but I wonder whether the larger brakes on the Spyder, the fronts are from the 991S and are 6 pots ( now standard on the 718S?), means a much lower wear rate than the 981S etc? Link to comment Share on other sites More sharing options...
jayk Posted September 1, 2016 Report Share Posted September 1, 2016 1 hour ago, temporarychicken said: In my experience EBC yellowstuff is only really entry-level as far as track-days are concerned, so a rest for the car every 25 min will be prudent! I'm not expecting racing level (continuous) endurance with this setup! The latest compound for yellowstuff has lasted 2.5 track days on another car of mine earlier this year. The road manners on yellowstuff are excellent too nowadays, so as a relatively inexpensive one size fits all pad they are okay at the price. CL are not made in my pad shape but Pagid RS29 are - albeit expensive. The ultimate upgrade for the track on this car would likely be RS29 plus the castrol fluid - as you have already discovered, but we are taking triple the budget of what I've done here and road manners would likely be compromised, esp for winter driving. Thus far I've not even boiled the standard Porsche brake fluid. I think @Buzzfox had had issues with fluid though in his GTS. I have a track day on the 24th so we will see how this upgrade holds up! I guess it depends on application, if your doing more road and less track, and smaller stints, but if your on a heavy breaking circuit Im sure they will not last long if you really are hammering the brakes, but as you said would be interesting to see. Let us know how they behave. Where are you tracking on the 24th? Quote Link to comment Share on other sites More sharing options...
Tony Daniel Posted September 1, 2016 Report Share Posted September 1, 2016 9 minutes ago, JohnSyn said: Really informative article, thanks for this. I've only tracked mine once so far, another day next week, but have looked at the pads on my car and they don't seem to have worn much. I will look again after the track day next week but I wonder whether the larger brakes on the Spyder, the fronts are from the 991S and are 6 pots ( now standard on the 718S?), means a much lower wear rate than the 981S etc? At Anglesey in May one of the Spyder owners told me he was going through a set of rear pads per trackday, something to do with the Porsche Torque Vectoring system...and him driving like a loon . Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 I'm at Bedford GT - a horrible circuit for your brakes! The reward for getting quicker and quicker round the twistier parts is loads more speed to take off at one of about 5 mega braking points. That's a disadvantage of Bedford. At Bedford I will be resting after every four laps and checking the pads. If the yellowstuffs can't indeed hack it then I will have to spend mega-money on Pagid RS29. We will see! The best circuit for brakes seems, rather ironically, to be the Nurburgring - if you know how to drive properly (not that I do yet) it there are relatively few braking points and much more throttle modulation. I once had a lesson there where I followed the Ringtaxi round for 3 laps. Very little braking going on there and it's very counter intuitive at first, but he was only at 7/10 of grip at best. Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 2 minutes ago, Tony Daniel said: At Anglesey in May one of the Spyder owners told me he was going through a set of rear pads per trackday, something to do with the Porsche Torque Vectoring system...and him driving like a loon . I heard a similar story. I think the Porsche Torque vectoring works by applying brakes to the inner wheel in a tight turn to turn the car into the corner more. Nice feature, but of course increases wear on the rear pads. Link to comment Share on other sites More sharing options...
spyderman8 Posted September 1, 2016 Report Share Posted September 1, 2016 A guy on the Porsche Club forum had the PCCBs wrecked on his 997.2 Turbo by PTV. Was not happy at how much he had to shell out to replace rear pads and discs. And there's no way you can turn it off. Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 That is a 3.5k pounds repair I think at least! I would have hoped that PCCB would have been an end to all brake problems on the track. If not, then what's the point?? It would be very galling to spend big money on 2 super expensive options (PCCB and PTV), and 1 kills the other. The only winner there is Porsche Service! Luckily my car is unencumbered by these options but the fact is that these are relatively heavy cars in road trim. Any car over 1 metric tonne will struggle brake-wise. Link to comment Share on other sites More sharing options...
edc Posted September 1, 2016 Report Share Posted September 1, 2016 It's interesting that while you experienced high pad wear on the track, the temp of the pad can't have been that high as you didn't report the brake sensor going off through melting. Ironically, on OE spec Textar front pads on my previous 986S I managed to get enough heat into those pads to melt the sensor yet the pads lasted the whole week easily. In terms of the brake electronic systems, it's interesting to note that a lot of the newer front drive hot hatches apply the rear brakes a lot too. On our Europe trip, aside from those cars needing a mid week brake pad change, the rears wore faster than the fronts. Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 Ed, where is the brake temperature sensor located? Does it illuminate on the dash, or merely store a fault code if triggered? Link to comment Share on other sites More sharing options...
Tony Daniel Posted September 1, 2016 Report Share Posted September 1, 2016 They are wear sensors not temp, but melt with track use. I dont fit them in the RS19 for that reason Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 Oh I see, Ed was referring to the wear sensors. I also deleted these during the work yesterday. Link to comment Share on other sites More sharing options...
jayk Posted September 1, 2016 Report Share Posted September 1, 2016 54 minutes ago, temporarychicken said: I'm at Bedford GT - a horrible circuit for your brakes! The reward for getting quicker and quicker round the twistier parts is loads more speed to take off at one of about 5 mega braking points. That's a disadvantage of Bedford. At Bedford I will be resting after every four laps and checking the pads. If the yellowstuffs can't indeed hack it then I will have to spend mega-money on Pagid RS29. We will see! The best circuit for brakes seems, rather ironically, to be the Nurburgring - if you know how to drive properly (not that I do yet) it there are relatively few braking points and much more throttle modulation. I once had a lesson there where I followed the Ringtaxi round for 3 laps. Very little braking going on there and it's very counter intuitive at first, but he was only at 7/10 of grip at best. I thought if it was local i could pop down and say hi, but its some distance. Never done Bedford as Donington or Oulton are my locals. - Yeah there are very few big braking points and you can carry speed through the bends and after big braking zones you have quite abit of time before getting on the brakes again. I took my brothers Civic Type R EK9 1.6 185hp to the Ring a few years ago, the car was pretty much standard but i put RBF600 and YellowStuff pads in, after half a lap i was getting some fade, this would clear but by then you've lost confidence when you come to the next big stop, still managed a 8:55. Link to comment Share on other sites More sharing options...
edc Posted September 1, 2016 Report Share Posted September 1, 2016 37 minutes ago, temporarychicken said: Oh I see, Ed was referring to the wear sensors. I also deleted these during the work yesterday. Yes, as Tony says above. Normally if you have enough heat in the pads the wear sensor will melt. That you didn't melt them suggests the pad was not up to the high temps. Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 They didn't met as the pads wore down to the point of triggering them before they could melt! Link to comment Share on other sites More sharing options...
edc Posted September 1, 2016 Report Share Posted September 1, 2016 12 minutes ago, temporarychicken said: They didn't met as the pads wore down to the point of triggering them before they could melt! I had brand new Textars in and within 36 hours in the Alps they melted, so well before they reach the usual wear point to trigger them! Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 I'm beggining to the think that the Alps is worse than Bedford GT! Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 1 hour ago, jayk said: I thought if it was local i could pop down and say hi, but its some distance. Never done Bedford as Donington or Oulton are my locals. - Yeah there are very few big braking points and you can carry speed through the bends and after big braking zones you have quite abit of time before getting on the brakes again. I took my brothers Civic Type R EK9 1.6 185hp to the Ring a few years ago, the car was pretty much standard but i put RBF600 and YellowStuff pads in, after half a lap i was getting some fade, this would clear but by then you've lost confidence when you come to the next big stop, still managed a 8:55. It's a shame you can't come down. We have three Boxsters confirmed already - one is a GTS like yours.! Link to comment Share on other sites More sharing options...
edc Posted September 1, 2016 Report Share Posted September 1, 2016 4 minutes ago, temporarychicken said: I'm beggining to the think that the Alps is worse than Bedford GT! In some sense it is. The descents can be long, there is no stopping (unless your brakes give up), plus you have the high ambient heat of August/September. You can be talking 15-30 hairpin or similar turns packed into a relatively short space. But if you do this several times a day over the course of a week you need good brakes! Link to comment Share on other sites More sharing options...
jayk Posted September 1, 2016 Report Share Posted September 1, 2016 12 minutes ago, temporarychicken said: It's a shame you can't come down. We have three Boxsters confirmed already - one is a GTS like yours.! Hmmm, might have to pop down and say hi, maybe get some passenger laps if you guys have space - Im off to Scotland a few days after your track day for abit of a Hoon, Link to comment Share on other sites More sharing options...
temporarychicken Posted September 1, 2016 Author Report Share Posted September 1, 2016 You would be most welcome to come to show us the car, and PAX with us! Pax fees are not too expensive. Link to comment Share on other sites More sharing options...
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