STOP!!! Let's Talk About Brakes ;-P

[6Spd_M]

So, I've put a fairly substantial amount of money into this car, mainly in suspension and safety. It is a dedicated HPDE car, running absolutely every SPL suspension component, a great coilover setup, professionally corner balanced, aligned, and tuned. I'm on a BM3 Stage 1 tune, only power mods are intake and cat back exhaust. Two different Apex wheel configurations both with R7's mounted.

So, I'm already planning my winter mods (crank hub, motor mounts, clutch, cooling updates, full exhaust, bm3 stage 2, wheel bearings all around) But the one thing I'm still NOT doing... Brake Calipers

I have talked to a LOT of guys on track and on forums, instagram, etc. who have had a very high level of hatred for the OEM calipers. I'm two really rough seasons in on my car, running OEM calipers... and I think they're great! They've not turned color, hardly ever have major brake fade (always just a little bit after 2 laps or so), and honestly have dealt with a lot of beating.

I'm not slow either! I'm running consistently the fastest times out of all cars every HPDE event by sometimes 1-2 seconds. This past Monday (6/24) I ran Pocono and was still 0.35 secs up on the next guy. And they're all running full blown 600+hp Z06 race cars. I was PUSHING a 2019 GT3RS (just not on the straights)

I'm regularly 1:09's at NJMP Lightning, 1:23's at Thunderbolt and 1:55's at Pocono (north south option 3).

I'm running Paragon 2-piece rotors, Paragon R5 pad compound (R7 is there most aggressive), Paragon Titanium shims, MOTUL 660 fluid, and stainless braided lines. Zero additional cooling/ducting.

I guess the moral of the story is this: I'm conflicted if I should invest in a big brake kit if I'm doing so well with the OEM calipers. Even after a LONG and very fun day at Pocono my driver side caliper was the hottest, but still only up to the 330F mark.

Someone please talk me into a proper big brake setup so I can justify the cost. PLEASE!!!!

brakes by Matt Kinsey, on Flickr

[SYT_Shadow]

If you haven't turned them green or black, you are not using them enough and you will not benefit from a race bbk. Keep doing what you're doing. Once they're black, you will benefit.

[jfritz27]

Matt, those are wicked fast times at NJMP, very impressive (do you have any vids with data up?? Please do so if not!!). I've never been to Pocono

I'm pretty far away from your pace, but my thoughts are that some of this depends on the track. TBolt for example is really not brake-intensive at all (only 1 big brake zone on a decently-sized track). Lightning is more so (2 big brake zones on a shorter circuit). So your lack of caliper discoloration may be driven in large part by that. I'm curious, at what brake marker are you hitting the pedal for T1 at Lightning and TBolt? I guess the question for you is whether a BBK would allow you to go deeper than what you are now...

[D_SheerDrivingPleasure]

Save your money. Here's a photo of my front caliper from last year after 3 track seasons. Most of my events are at Lime Rock Park which is also gentle on the brakes. I use Ti shims, girodisc rotors, racing brake high temp seals/dust boots and removed spash sheilds. This year I added the Bimmerworld deflectors ($150). A BBK is pretty but it's probably not necessary for you.

[6Spd_M]

Originally Posted by jfritz27

Matt, those are wicked fast times at NJMP, very impressive (do you have any vids with data up?? Please do so if not!!). I've never been to Pocono

I'm pretty far away from your pace, but my thoughts are that some of this depends on the track. TBolt for example is really not brake-intensive at all (only 1 big brake zone on a decently-sized track). Lightning is more so (2 big brake zones on a shorter circuit). So your lack of caliper discoloration may be driven in large part by that. I'm curious, at what brake marker are you hitting the pedal for T1 at Lightning and TBolt? I guess the question for you is whether a BBK would allow you to go deeper than what you are now...

Thunderbolt: I'm hard on the brakes right where the red and white curbing starts on the left side. I think it's just before the 3 marker, but could be wrong. To be honest I don't look at the brake markers very much, I typically choose a visible feature on the track surface, or sometimes a "feel" feature on the track. i.e. the brake zone into T1 at lightning there's two "humps" in the track in the braking zone. I'm off the gas, hit the two "humps" and then hard brake. Again, I think these are right about at the 3 marker.

[jfritz27]

Originally Posted by 6Spd_M

Thunderbolt: I'm hard on the brakes right where the red and white curbing starts on the left side. I think it's just before the 3 marker, but could be wrong. To be honest I don't look at the brake markers very much, I typically choose a visible feature on the track surface, or sometimes a "feel" feature on the track. i.e. the brake zone into T1 at lightning there's two "humps" in the track in the braking zone. I'm off the gas, hit the two "humps" and then hard brake. Again, I think these are right about at the 3 marker.

So that's reasonably late braking there if you're around the 3-markers. And your laptimes are quick. If you're not feeling fade, then I guess question remains as to whether you could confidently brake later with a BBK. It's honestly hard to imagine you could go later given the decel delta you're needing with your tuned setup (at Lightning T1, for example), but I guess maybe.... if it were me I think I would only consider doing this if I were fairly convinced there was no additional time to be gained elsewhere

Did you mention somewhere else that you're going to a stiffer suspension? If that is your plan, I would definitely wait to see what braking gains that may bring before splurging on the BBK

[noemon]

I'm surprised you 're not feeling more fade.

I was out at Bedford Autodrome last week pushing the car a bit more than usual and the fade eventually became quite significant.

I was on your wave-length up until that point but in hindsight I was managing them constantly with 2-3 laps and then cooling lap, rinse, repeat. Last week I pushed to 4-5-6 laps instead and the brakes faded quite a bit.

Luckily I found a used set of Alcon Super Kit front with Pagid rsl29's and 400mm rotors and grabbed them, now I'm no longer managing the brakes every 2-3 laps and also brake much later.

However, I'm having trouble pairing them with 18's, which has now become my new big issue so also thinking of reselling them and going for AP's with smaller rotors so I can stick with my 18's.

[6Spd_M]

Originally Posted by jfritz27

So that's reasonably late braking there if you're around the 3-markers. And your laptimes are quick. If you're not feeling fade, then I guess question remains as to whether you could confidently brake later with a BBK. It's honestly hard to imagine you could go later given the decel delta you're needing with your tuned setup (at Lightning T1, for example), but I guess maybe.... if it were me I think I would only consider doing this if I were fairly convinced there was no additional time to be gained elsewhere

Did you mention somewhere else that you're going to a stiffer suspension? If that is your plan, I would definitely wait to see what braking gains that may bring before splurging on the BBK

Yeah, MCS 3-way remotes are on order very very soon. Still working out spring rates as I'll have a very aggressive front splitter and rear wing. Want to run a dual spring setup to allow the aero to do it's work.

You're probably right to go all out on the suspension and aero, then see where I'm at with the brakes.

Might just say screw it and go all out and order a bbk anyway. Rather have it and not use it to it's full potential than not have it and need it desperately.

[6Spd_M]

Originally Posted by noemon

I'm surprised you 're not feeling more fade.

I was out at Bedford Autodrome last week pushing the car a bit more than usual and the fade eventually became quite significant.

I was on your wave-length up until that point but it in hindsight I am fairly certain that I was not getting fade before simply because I was managing them constantly with 2-3 laps and then cooling lap, rinse, repeat. Last week I pushed to 4-5-6 laps instead and the brakes faded quite a bit.

Luckily I found a used set of Alcon Super Kit front for £1400 with Pagid rsl29's and 400mm rotors and grabbed them, now I'm no longer managing the brakes every 2-3 laps and also brake much later.

However, I'm having trouble pairing them with 18's, which has now become my new big issue so also thinking os reselling them and going for AP's with smaller rotors so I can stick with my 18's.

Honestly, I've run quite a few combinations of pads/rotors. This Paragon pad/shim/rotor setup is amazing. They've recently redesigned the rotor for better cooling too, which improved an already awesome product.

[jfritz27]

Originally Posted by 6Spd_M

Yeah, MCS 3-way remotes are on order very very soon. Still working out spring rates as I'll have a very aggressive front splitter and rear wing. Want to run a dual spring setup to allow the aero to do it's work.

You're probably right to go all out on the suspension and aero, then see where I'm at with the brakes.

Might just say screw it and go all out and order a bbk anyway. Rather have it and not use it to it's full potential than not have it and need it desperately.

Dual spring setup? Interesting... Meaning like a small tender then a standard linear main spring? I considered something like this in search of a more compliant street ride, but from when I was searching, I couldn't find any short helpers with the kind of helpful rate that wouldn't be coil-bound at static height given the typical corner weights of this platform (also issue of stack height/perch location and impact on fitting wide rubber up front). Would be interested to hear what you're kicking around on this...

[6Spd_M]

Originally Posted by jfritz27

Dual spring setup? Interesting... Meaning like a small tender then a standard linear main spring? I considered something like this in search of a more compliant street ride, but from when I was searching, I couldn't find any short helpers with the kind of helpful rate that wouldn't be coil-bound at static height given the typical corner weights of this platform (also issue of stack height/perch location and impact on fitting wide rubber up front). Would be interested to hear what you're kicking around on this...

I don't need this FULL package, but this would be the ideal coilover/spring setup:

https://www.bimmerworld.com/GTMore-S...F8X-M3-M4.html

[jfritz27]

Originally Posted by 6Spd_M

I don't need this FULL package, but this would be the ideal coilover/spring setup:

https://www.bimmerworld.com/GTMore-S...F8X-M3-M4.html

That's the top shelf for sure... though it's not a dual spring setup (other than having a near zero-rate helper to keep everything seated at droop)

Just as an FYI, when I went to 3w MCS I actually wanted to get the GTmore MCS-only (without the custom SPL arms). That setup requires you to obviously use the special BW Clevis-style camber plate (a very slick design). But there's a supposed problem in going that route WITHOUT also doing the GTmore SPL arm package, because the Clevis plate geometry is designed to work in concert with the custom SPL arms to pull the entire damper/kingpin assembly inward, to allow for fatter tires. If you only do the dampers/Clevis plate but not the arms, then the top end gets pulled in but the bottom end doesn't, so according to BW that induces weird geometry changes that weren't planned for the package as a whole, and they didn't recommend going that route (despite selling the GTmore dampers separately, which is weird).

[uncle ben]

Tough call on the brakes. I’m considering a bbk as well. When you start considering the cost to maximize the stock calipers (stainless pistons, ti shims, Girodisc rotors, racing pads, ducting) the costs can get you close to a used bbk. I also haven’t noticed any fade or any caliper discoloration, but it may be my driving or the tracks I drive. Hopefully a good deal on a bbk comes along for us both and makes the decision easier.

[6Spd_M]

Originally Posted by uncle ben

Tough call on the brakes. I’m considering a bbk as well. When you start considering the cost to maximize the stock calipers (stainless pistons, ti shims, Girodisc rotors, racing pads, ducting) the costs can get you close to a used bbk. I also haven’t noticed any fade or any caliper discoloration, but it may be my driving or the tracks I drive. Hopefully a good deal on a bbk comes along for us both and makes the decision easier.

What tracks are you driving? I'm interested to see if we're both just in this strange scenario of being on non-brake-heavy tracks.

[D_SheerDrivingPleasure]

Before upgrading to a BBK, consider that most do not have dust seals. This is a major downside if you live in a region with road salt/grime.

[uncle ben]

Originally Posted by 6Spd_M

What tracks are you driving? I'm interested to see if we're both just in this strange scenario of being on non-brake-heavy tracks.

I’m located in Canada, but the few tracks I drive are described as “easy on brakes” so I’m assuming they are.

[FrankMstein]

I would put one of those temp strips on a rear caliper. Mine run hotter than front with MDM on and TC off. I get traction light flicker with MP4S and BM3 OTS2. I also have cooling on the front rotor and not on the rear. Will be getting the track cooling setup from Sweden when they make them for CCB. Mine is a lightly (5-7/10ths) driven instruction car. Temps are 250F on the front and 280F on the rear at 7/10ths.

BTW you will only see VERY slight power increase with OTS2 from 1 in the 2-3500rpm and faster spool.

[Vmohan5072]

Originally Posted by jfritz27

Matt, those are wicked fast times at NJMP, very impressive (do you have any vids with data up?? Please do so if not!!).

I was thinking the same! I'm still over here sitting at 1:19 in a fully stock car, seeing 1:09 is astonishing and I would love to find ways to get anywhere near close to that (Skill wise, I gotta do better tires, camber, and probably coils to even see close to it)

On the main topic, I agree with the others. BBK likely not needed yet. Try the bimmerworld brake cooling duct and see if that helps

[MAG22]

This is what I heard from BW as well and I am super frustrated about it. I really wanted a system to build myself up to. I understand things won’t work optimally until all components are installed, but I should be the one that decides what components are best for me at the time. What is so magical about the SPL arms in the GTM package anyway? Seems to me that they are just different lengths and adjustment ranges than the normal arms. So theoretically, can someone just get the measurements of each arm so we can order directly from SPL? Don’t get me wrong, I love BW, but they should offer all components separately

Originally Posted by jfritz27

That's the top shelf for sure... though it's not a dual spring setup (other than having a near zero-rate helper to keep everything seated at droop)

Just as an FYI, when I went to 3w MCS I actually wanted to get the GTmore MCS-only (without the custom SPL arms). That setup requires you to obviously use the special BW Clevis-style camber plate (a very slick design). But there's a supposed problem in going that route WITHOUT also doing the GTmore SPL arm package, because the Clevis plate geometry is designed to work in concert with the custom SPL arms to pull the entire damper/kingpin assembly inward, to allow for fatter tires. If you only do the dampers/Clevis plate but not the arms, then the top end gets pulled in but the bottom end doesn't, so according to BW that induces weird geometry changes that weren't planned for the package as a whole, and they didn't recommend going that route (despite selling the GTmore dampers separately, which is weird).

[D_SheerDrivingPleasure]

Originally Posted by Vmohan5072

I was thinking the same! I'm still over here sitting at 1:19 in a fully stock car, seeing 1:09 is astonishing and I would love to find ways to get anywhere near close to that (Skill wise, I gotta do better tires, camber, and probably coils to even see close to it)

On the main topic, I agree with the others. BBK likely not needed yet. Try the bimmerworld brake cooling duct and see if that helps

1.09 is ludacrous speed.

Yes to the Bimmerworld brake deflector kit. I should have tried the temp testing strips things before and after installing. In any event, they BW kits is inexpensive, easy to install and compromise free (no wheel/tire interference).

[jfritz27]

Originally Posted by MAG22

This is what I heard from BW as well and I am super frustrated about it. I really wanted a system to build myself up to. I understand things won’t work optimally until all components are installed, but I should be the one that decides what components are best for me at the time. What is so magical about the SPL arms in the GTM package anyway? Seems to me that they are just different lengths and adjustment ranges than the normal arms. So theoretically, can someone just get the measurements of each arm so we can order directly from SPL? Don’t get me wrong, I love BW, but they should offer all components separately

Yeah, in retrospect maybe I should have pushed a little harder on the "why" (or asked to talk to Phil directly)... but in the end I trusted them as generally they know what they're talking about, and they could have more easily upsold me on the more expensive option. The obvious thing if you went with GTmore damper/topmount but not the custom arms is that you'd put more negative camber into the setup, perhaps so much that if you're like me and do the street/track camber switcharoo, you'd not be able to achieve enough relative positive (less negative) camber for your street setting (constrained to an overall higher negative camber working range). But the implication it seems from them is that it's somehow more than that.

[b_w.]

Originally Posted by MAG22

This is what I heard from BW as well and I am super frustrated about it. I really wanted a system to build myself up to. I understand things won’t work optimally until all components are installed, but I should be the one that decides what components are best for me at the time. What is so magical about the SPL arms in the GTM package anyway? Seems to me that they are just different lengths and adjustment ranges than the normal arms. So theoretically, can someone just get the measurements of each arm so we can order directly from SPL? Don’t get me wrong, I love BW, but they should offer all components separately

I pushed them on that before ordering the gtmore kit. I was told that the arms suck the hub in so far that with regular camber plates you would end up with positive camber. The eye to eye mount plates move the mounting point very far inwards. I can take pics if anyone wants.

If you want to order shorter arms I believe spl will do custom lengths. I have seen where some guys cut the strut brace to get more room to increase camber.