Do you still care about noise?
I'd throw G-LOC R10 front and R8 rear in it and call it a day. The only thing to note is that they'll be noisy. I'm running the G-LOC R6 in my Wilwood FSLI4 calipers and they're stupid noisy at any speed below 20 MPH, so much so I got the GS-1 compound for them in hopes to mitigate the noise.
I run R12/R10 F/R for track. I swap wheels for the track and swapping pads is trivial. I'd strongly recommend a 2 pad set up if it's possible, otherwise the G-LOC pads are your best bet imo. When paired with a proper brake cooling solution they'll last quite a while in my experience.
I can put up with some low-speed whining, but I've heard brakes that make a horrible screeching any time you use them and I don't want that.
I did the same FIRM track day in my ND Miata (non-Brembo) on Power Stop Track Day PSA pads. I already told Richard, but my experience was very positive. No fading and plenty of stopping power all day, despite lap after lap of hard driving. On the street they behave well, with good OEM-like initial bite, no extra pedal effort, and they rarely ever squeak, but they dust like CRAZY. All four stock rotors still look good and smooth.
I drove Road Atlanta yesterday and the brakes still held up great, even during that infamous Turn 10 downhill back straight braking zone. Compared to when I did Road Atlanta a few months ago on the OEM pads and fluid, I had a lot more confidence in braking later and doing multiple hot laps in a row without any fade. Some of that was certainly due to the Motul RBF 600 fluid. Side note: not sure if this is normal, but even with a cooldown lap before pitting, the pedal was a little softer after letting the car sit a bit. I assume that's just heat soaking into the fluid from lack of airflow when sitting.
Due to my vain love of clean shiny wheels, I will be swapping them out for the OEM pads until my next track day. I plan to take measurements to track wear and pump in some fresh fluid.
GameboyRMH said:
I can put up with some low-speed whining, but I've heard brakes that make a horrible screeching any time you use them and I don't want that.
I love squealy brakes. I hated having to take them off for winter.
In reply to GameboyRMH :
R10/R8 should be your best bet then. I can't stand low-speed squeal. I thought I could but it's incredibly annoying.
In reply to hunter47 :
What do you think about R8s all-around? I'm thinking the R10s may be overkill for the front, the PSTs were nearly good enough and those are more of an aggressive street pad/super-mild track pad.
GameboyRMH said:
In reply to hunter47 :
What do you think about R8s all-around? I'm thinking the R10s may be overkill for the front, the PSTs were nearly good enough and those are more of an aggressive street pad/super-mild track pad.
I have no input on this specifically, but I wanted to mention that R10's up front gave me some, ah, tight-cheeked moments while street driving in cool weather (~40F). After not touching the brakes for several miles that first pedal press is not particularly effective.
GameboyRMH said:
In reply to hunter47 :
What do you think about R8s all-around? I'm thinking the R10s may be overkill for the front, the PSTs were nearly good enough and those are more of an aggressive street pad/super-mild track pad.
Should be fine on a light car.
In reply to hunter47 :
What kind of cars are y'all running with the R10/R8 (XP10/XP8)? I ran that combo on the S2000 in dual-duty and they were probably the loudest pads I've had mounted on it.
Parker with too many Projects said:
In reply to hunter47 :
What kind of cars are y'all running with the R10/R8 (XP10/XP8)? I ran that combo on the S2000 in dual-duty and they were probably the loudest pads I've had mounted on it.
I'm not running dual duty R10/R8. I have R12/R10 track and R6/R6 (soon to be GS-1/R6 for reasons stated earlier) for street. They're noisy at low speeds which can be fine for some people but not me, evidently. 2020 WRX.
So after much deliberation, I've decided to turn up pad aggressiveness just 1 notch and ordered a set of PSAs. These will need the least warmup of all the options and I'm pretty confident they'll hold up on the front, not so confident about the rear but hopefully with ducting added on the rear axle as well, there won't be any more rotor destruction...
Update: So far the only difference between the PSAs and the PSTs noticeable from the driver's seat is that the PSAs are a bit noisier, plenty of low-speed whining but it's not too bad. From outside, the first noticeable difference is dust. If the PSTs were the arch-nemesis of the person who wants their wheels to be clean, the PSAs are this person's anime arch-nemesis' final form. A track night on the Shannonville Nelson short course painted the front wheels matte black with dust and barely left a hint of bronze visible on the rear. They still performed well though and the discs may have been darkened slightly by pad material but otherwise looked no different from street use. Doing the Challenge autocross & drags had the same result. The next big test would be the GRM track day at the FIRM. Here they performed similarly to the PSTs again, but with less noise. I did notice that they seemed to be less bitey at higher temperatures although performance under ABS engagement stayed consistent. The wheels were fully blackened with dust once again as expected by now, the discs definitely survived this time with some light grooving in the rear and the same in the front plus some light surface cracking which can be seen here:
https://grassrootsmotorsports.com/forum/grm/critique-my-brake-disc-condition/254429/page1/#post3730153
There is also already a noticeable lip on the front discs that were put on in March, on top of the Challenge events they've only seen a few autocrosses and the track night.
The brake fluid level dropped noticeably from the GRM track day so I expect that a chunk of the pad material is gone, I'll see how much next time I have the wheels off.
I finally experienced fade on my Powerstop PSA pads at AMP yesterday. No "oh-E36 M3" moments, but definitely way less stopping power about 10 minutes into each session. I need to take them off and measure thickness, but I am guessing they are simply too thin now. The fronts had worn by 2mm after last year's FIRM and Road Atlanta, and since then I've done two track nights at AMP, another at Road Atlanta, some autocrosses, plus a few thousand miles commuting once I got lazy about swapping pads. I can also tell visually that my rotors are wearing quickly too, with what looks like some dishing. I will measure and replace if necessary. Despite the dust they have remained silent since day one, no squeaking. Very satisfied overall.
I convinced a friend to start tracking his C6 Vette, and he too went with the Power Stop track day pads. So far his experience is also positive, but his make a ton of noise during normal daily driving.
I measured my fronts to have about 8mm of pad material left after this year's post-Challenge FIRM track day and 2 Shannonville short course track nights, plus the rest of the Challenge and some other autocrossing. Did another track day at Mosport DDT and a few more autocrosses since then and they've held up well so far, I haven't measured them again yet. I've noticed decreased bite at high temps but no trouble engaging ABS, however sometimes there's a noticeable increase in the amount of pedal force needed to get there. I do have added brake cooling, Porsche GT3 scoops in the front, and backing plates cut & bent into a scoop shape in the rear. I've only had some light whining at low speeds. Disc wear hasn't noticeably increased since June, it could be that break-in or the brake-brutalizing conditions on the FIRM caused a lot of it.
Measured the pads again today, last measurement was just before the DDT track day, there's about 5mm of material left so maybe 1 more track day left in them at most, I expect they're going to become useless for track work once they're down to about 3mm.
Looked at ordering replacements and I'm worried that the rears might be going out of production, the PSA-1124s are out of stock most places and backordered on the few where they aren't. If I can't get those I could try something more aggressive on the rear, it seems that the rears run about as hot as the fronts on this car and wear down at a similar rate, if they need some warmup it wouldn't have as much effect on braking overall.
Did a wheel rotation today and took the pads out, noticed that on one side the front pads were unevenly worn (about 4mm per pad all-around, but one side wore down slanted) and probably too thin to make it to next year in some spots, so I put a fresh set of PSAs on the front and freshened up the slider grease, the rears still have about 4mm of material so should be good for 1 more track day, I'll change those at the start of next season.
So the PSAs didn't quite make it through a fairly conservative race season...the front discs are also probably close to finished too, they're 24mm thick when new, 22mm minimum, and the lips on them look like they're close to 1mm now. I think I'll have to look for local options that might be cheaper than getting discs shipped from RockAuto. The Centric GCX coating isn't a whole lot better than paint so I think I'll try to find some plain Centrics locally and paint them myself.
Looking at pad options again because there are definite problems sourcing the PSAs for the rear. I ordered them from one of the few places that claimed to have them in stock, I was originally supposed to get them in September, now I'm looking at February. If there's another delay I'll just have to try something else, I'm thinking something more track-pad-like.
I noticed you can get some fade on the PSAs on long stints, ABS still engages but it takes a lot more pedal force and you can feel that there's some ramp-up time.
Also had an oh-E36 M3 moment with the PSAs in freezing weather, I'd been cruising the 401 without using the brakes for a while, hardly even used them before getting on the highway, so the brakes might've been literally ice cold. Traffic started to slow down suddenly. So I hit the brakes and got none for a second! They kicked in pretty quickly after that but they do need to be above freezing to work.
Here's my little table of brake pad options I've put together (sorry for spacing, seems the forum doesn't like tab breaks):
Model Front PN Rear PN Comment
Raybestos ST43 RC 1539 R 1124.16 Crazy expensive! Great performance and last long though
Pagid RSL29 RSL29 8174 RSL29 8175 Tom Suddard runs these, weak when cold, also noisy!
Powerstop PSA PSA-1539 PSA-1124 Good cold performance, fairly cheap, low noise, but wears fast, eats discs, super dusty, can fade a bit. Slow to order
Stoptech 309 Sport ST-309-15390 ST-309-11240 Cheap! On GRM's dual-duty E46
Winmax W3 WMP580 WMP655 ae86andkp71 runs these. Fairly cheap, supposed to be low dust, made to order
Porterfield R4 R4 AP1539 R4 AP1124 Bobzilla runs these, good when cold
Porterfield R4-E R4-E AP1539 R4-E AP1124 Lower friction but longer wearing than R4
Ferodo DS2500 FCP1639H FCP4187H Similar to ST43, maybe more street-oriented...but also very expensive
G-LOC R8 R8 GP929 R8 GP1124 200F min operating temp
EBC Bluestuff NDX DP51884NDX DP51584NDX Wider temperature range and easier break-in than Yellowstuff, wears fast though
GameboyRMH said:
Ferodo DS2500 FCP1639H FCP4187H Similar to ST43, maybe more street-oriented...but also very expensive
Having owned both, these are in no way comparable to the ST43. The 2500s drive more like an OEM pad that doesn't fade, and they wear out very quickly at trackday temperatures. Ferodo's DS 1.11 are similar but the pedal feel is softer.
I also had a hard time sourcing PSAs for my ND Miata, so I said berkeley it and now I switch pads/rotors for the track. I went with Hawk DTC. If I plan ahead, I can do it during the work week, and only have to commute a few times on the wrong brakes, plus the drive to and from the track.
Gameboy, as you're measuring pads and estimating life remaining, remember that thin pads will run hotter and wear faster.
dps214
SuperDork
12/28/23 12:54 a.m.
You list the other two r4 options, is the r4s available? Should be basically comparable to your current pads - cheap, quiet, good cold, *almost* enough temperature range for a track pad.
In reply to dps214 :
Yeah R4S is available, sounds like they might be a bit more street-oriented than the PSAs though...Porterfield doesn't recommend the R4S for track use.
I ran the R4S on my NC Miata at Sonoma. They worked pretty well and held up admirably but after getting the track down when I was ready to move up a run group it was seeming like they weren't enough anymore. For a small/light car on a short/small track they are probably enough but I would go for the R4 if you don't need them to be livable for street driving.
I ran the Gloc R12 front with the previous year's R4 in the rear. Aggressive bite, even cold (and I mean actual cold, like 30*), consistent pedal. They do squeal (positive for me but I am weird) and make an assload of dust but they have held up well with street use. I am planning on driving the Rio tomorrow, still wearing those. The worst part of the drive will be the A/S tires with 3.5* of camber
