Pure Motorsport: JDL Turbo BRZ Track Build

[ModBargains]

Originally Posted by was385

Is there any color that doesn't look great on the FRS/BRZ?

Right? Great car

[ATL BRZ]

I've been fortunate enough to have a LOT of track time available when I'm instructing and I've gotten a lot more so far this year than I thought I would, with more still to go. I've not experienced abnormal wear on my rotors, in fact I've only recently in February installed my first set of new front rotors since installing the cooling kit last year with 10+ track days on the car. The stock calipers are definitely not designed for the kind of heat I put them through on track. Even with titanium shims my dust boots can't take the heat and have begun to split around the pistons. Race pads with an 800*C MOT are getting so much heat into them they are glazing, crumbling away and wearing too quickly for my taste. I considered getting Winmax W7 or a slightly higher MOT race pad but they are still well over $200 a set in front and have a relatively thin friction puck in OEM sizing.

With my driving experience increasing I'm getting faster in the car, and with new coilovers going on soon my entry speeds will go up that much more and so will my braking demands. I have been progressively less confident with my OEM front brakes every time I track my car despite all the provisions I've made to them. Could I buy more expensive rotors and pads and try those out? Sure. But they wont add any more thermal capacity to the system as a whole and that's where I've finally hit my breaking point (pun intended). I've gotten to the point where my cost for consumables is hurting me with all the track time I'm getting, and my confidence is still going down. The stock braking system isn't designed for track usage and the air ducting is simply a crutch for the system, which is not very thermally efficient at all by design. It has not solved the issue of my lack of braking confidence and it never will. There is only so much braking power a floating 2-piston caliper and 24mm wide rotor can deliver and the demand I'm bringing to them on track has far exceeded their thermal capacity. It took me a while to admit all this to myself but now that I can finally afford a BBK, I'm coming to terms with it all and deciding to cut my losses before getting too deep in consumables in an already inefficient system.

I'm admittedly a hard sale. I must have read the Essex/AP Racing Sprint Kit product page 10 times over before I finally came to terms that the pros of the BBK far outweigh the one single con: high entry price. Cheaper, thicker pads, more compound variety, more braking power, no dust boots, huge increase in thermal capacity/efficiency, 20lbs overall unsprung weight reduction...etc. The bias also remains near stock as the piston sizes were custom from Essex with that requirement in mind.

So all that said, my BBK arrives tomorrow and I couldn't be more excited to get all these new parts on the car and back out on track.



I went with CL RC6 pads for track and Carbotech Bobcats (1521) for street use. I will be removing the Touge Factory brake cooling kit since the backing plates are not compatible with the fixed caliper design on the BBK. I may revisit ducting in the future but for now I'll likely pass my kit on to someone else who can benefit from it. To address brake cooling I've got a pair of Porsche 911 GT3 brake air guides...



...that will mount to the control arms in the same fashion they do on the GT3, only using zip ties for security
(credit to @makinen for pics and application)



As you can see below they are functional at drawing in air from the wheel wells at speed and redirecting it to the rotors.



To what measurable degree they will work is to be determined but all I know is for $34 shipped I'm not going to let all that air slip past my control arms without getting put to good use! I encourage others here to try them out as there only seems to be a few using them.

Tracking this car has been a learning experience for me and a very rewarding one at that. As I approach my 2nd year anniversary of ownership I'm reminded of how far this build has come and how and it's pretty humbling looking back at it all. I'm looking forward to getting back my lost braking confidence and having more mechanical grip from the new suspension and extra camber dialed in all around.

[King Tut]

I look forward to seeing how your AP rotors and pads hold up in the long run. The one thing I don't understand is how the OEM brakes on my 1987 BMW 325is running cheap $15 rotors and anything from Hawk DTC60 to PFC01 pads with no modifications other than removing the OEM heat shields hold up just fine to racing conditions and the BRZ is unable to do the same. The difference in weight is only on the order of 200 lbs. Are you sure that you aren't just going with too aggressive of a pad? Confidence is definitely more important than losing a couple feet of stopping distance in a braking zone.

[gramicci101]

Would using GT3 brake ducts on the rear as well be beneficial at all?

[ATL BRZ]

Originally Posted by King Tut

I look forward to seeing how your AP rotors and pads hold up in the long run. The one thing I don't understand is how the OEM brakes on my 1987 BMW 325is running cheap $15 rotors and anything from Hawk DTC60 to PFC01 pads with no modifications other than removing the OEM heat shields hold up just fine to racing conditions and the BRZ is unable to do the same. The difference in weight is only on the order of 200 lbs. Are you sure that you aren't just going with too aggressive of a pad? Confidence is definitely more important than losing a couple feet of stopping distance in a braking zone.

I've been running Project Mu Club Racer pads for a while now which are .42-.55 CF. They're are a step under the 999 and Winmax W7 and other "full race" pads. I don't think they are too aggressive, I think my experience is bringing me into corners with higher entry speeds than before and my braking demands are exceeding the stock fronts ability to dissipate the heat enough inbetween corners; even with the help of the ducting. I've had hints of fade before at all tracks but the ducting kept the temps under "control" before they would actually fade into the following corner. The glazing and accelerated wear still happens and it has recently been very uneven on the fronts. I actually had to swap the front pads left to right at Road Atlanta a couple weeks ago after seeing the driver's side pads worn several mm more than the passenger's side. I realize my titanium shims are trapping the heat in the pads and probably contributing to the accelerated wear but they are a catch-22 I deemed necessary to keep the heat out of the dust boots and ultimately the fluid. Like I said before I considered trying different pads but I'm not sure they'd make a big difference in performance and most importantly my confidence in the system as a whole.

I don't want to brake earlier and baby my brakes. I want to do the opposite

Originally Posted by gramicci101

Would using GT3 brake ducts on the rear as well be beneficial at all?

I don't think it's necessary since the rear brakes don't get nearly as hot as the fronts. I haven't experienced abnormal wear or heat issues with mine, nor have I heard any AP Sprint BBK owners deem the stock rear rotors and calipers as being incapable of track abuse on their own. Also the rear LCA on our cars doesn't have the same curved profile that allows the guides to work at the right angle and "scoop" the air towards the rotors. They are just flat.

[King Tut]

Originally Posted by ATL BRZ

I've been running Project Mu Club Racer pads for a while now which are .42-.55 CF. They're are a step under the 999 and Winmax W7 and other "full race" pads. I don't think they are too aggressive, I think I'm getting too aggressive on the pedal for the stock fronts to keep up. I've had hints of fade before at all tracks but the ducting kept the temps under "control" before they would fade into the following corner. The glazing and accelerated wear still happens and it has recently been very uneven on the fronts. I actually had to swap the front pads left to right at Road Atlanta a couple weeks ago after seeing the driver's side pads worn several mm more than the passenger's side. I realize my titanium shims are trapping the heat in the pads and probably contributing to the accelerated wear but they are a catch-22 I deemed necessary to keep the heat out of the dust boots and ultimately the fluid. Like I said before I considered trying different pads but I'm not sure they'd make a big difference in performance and most importantly my confidence in the system as a whole.

I might have it backwards then. Perhaps you aren't running enough pad and you are WAAAY overheating the pads. I thought I was fine on Hawk HP+ pads while I was doing HPDEs. That changed the day I got to Talladega GP a course with multiple brake zones and no straightaway to cool the brakes. I destroyed my pads at a rate I couldn't believe resulting in getting to the backing plate and then having my piston go through the baking plate till I lost the brake fluid behind it and had a total brake failure. The heat was just way too much for the operating range of those pads and the material went away very quickly. Perhaps just stepping up to a higher heat range pad would have given you that confidence back and kept the pedal firmer. I could see you doing the same thing with your AP setup depending on pad selection. I would recommend running a true track pad that is designed as an endurance type pad like a PFC06 or PFC08 so you won't overheat them and they should last as long as possible to keep consumable costs down.

[ATL BRZ]

Originally Posted by King Tut

I might have it backwards then. Perhaps you aren't running enough pad and you are WAAAY overheating the pads. I thought I was fine on Hawk HP+ pads while I was doing HPDEs. That changed the day I got to Talladega GP a course with multiple brake zones and no straightaway to cool the brakes. I destroyed my pads at a rate I couldn't believe resulting in getting to the backing plate and then having my piston go through the baking plate till I lost the brake fluid behind it and had a total brake failure. The heat was just way too much for the operating range of those pads and the material went away very quickly. Perhaps just stepping up to a higher heat range pad would have given you that confidence back and kept the pedal firmer. I could see you doing the same thing with your AP setup depending on pad selection. I would recommend running a true track pad that is designed as an endurance type pad like a PFC06 or PFC08 so you won't overheat them and they should last as long as possible to keep consumable costs down.

Yep, I'm pretty sure that's what's happening. I am already overheating 800C MOT pads. Unfortunately in stock sizing there aren't many choices out there with a much higher MOT that I've found. Winmax W7 goes up to 850C; thats about the highest I found but they have a slightly lower CF so the bite goes down a little bit, on paper at least. They are still more expensive and have a much thinner friction puck than the BBK pads.

A hotter pad still wouldn't completely solve the thermal efficiency issue as my entry speeds and braking demands inevitably increase proportionally to the new suspension coupled with amount of seat time I'm getting. The rotors would then likely become the weakest point. Do not want.

[Roxy86]

Interesting.
I ran those brake guides on my Evo X, never bothered trying them on the FR-S.
Good to know it fits.

Ran CL Brakes RC6's on my X.

[ATL BRZ]

Originally Posted by Roxy86

Ran CL Brakes RC6's on my X.

How did they perform? I've heard from others here that they are extremely durable, which is why I chose them for my first set of BBK track pads.

[Roxy86]

Originally Posted by ATL BRZ

How did they perform? I've heard from others here that they are extremely durable, which is why I chose them for my first set of BBK track pads.

I tried Carbotech XP12's last time around, since it was highly recommended by few local guys.
Initial bite on both pads RC6 and XP12's are similar, however pedal feels slightly firmer with CL's. Both pads feel well balanced under hard braking.
Personally I like to jab the brakes and RC6 felt better for my driving style.
Both withstood 20 min sessions equally well matched to my 265 ZII star specs. No fade.
Long term wise, I will go back to CL's, since buying front and rear pads are cheaper, and their bedding procedure is a cinch.

[makinen]

Originally Posted by gramicci101

Would using GT3 brake ducts on the rear as well be beneficial at all?

For the rear ducting, Arrows released rear brake ducts .
Those are CFRP and too expensive to cool not over-heating rear brakes.



(I cant remember where I've got this image. Sorry)

[ATL BRZ]

Originally Posted by makinen

For the rear ducting, Arrows released rear brake ducts .
Those are CFRP and too expensive to cool not over-heating rear brakes.

They look good but I agree they aren't necessary. In that pic the splash guards are still present behind the rotors.

Wouldn't that block all the air from those ducts?

[makinen]

Originally Posted by ATL BRZ

They look good but I agree they aren't necessary. In that pic the splash guards are still present behind the rotors. Wouldn't that block all the air from those ducts?

No problem at all because it's not overheating!

[ModBargains]

Ridiculous diffuser!