BMW Performance Brembo 6-Piston BBK from the 135i

[S14]

People here seriously underestimate the stock brakes...

I have CSL brakes all around with hawk DTC-70s and RBF 660 (both free from FCP. Gotta give them a shoutout whenever possible). My car is stock weight. I'm comfortable in any intermediate group on slow tracks with LOTS of braking and on fast tracks with lots of cooling time but hard braking zones (road america for example). 30 min sessions always. I have never had brake fade. Never had bad pedal feel. Never wished my brakes were better. Never had a complaint honestly. That being said, I have not driven with a true BBK. I keep looking for a reason to switch over, but my current setup doesn't seem to have flaws. Could I be braking later? Am I simply missing out on pedal feel?

Am I missing something? Or am I just too slow?

What tires are you running?

My reason for wanting to do the 996 calipers is less unsprung weight, easier pad changes at the track, and FCP warranty.

[SteelGreyM]

What tires are you running?

My reason for wanting to do the 996 calipers is less unsprung weight, easier pad changes at the track, and FCP warranty.

PS4S. Although, I’m at their limits. They are what’s holding me back from going faster right now.

[Obioban]

People here seriously underestimate the stock brakes...

I have CSL brakes all around with hawk DTC-70s and RBF 660 (both free from FCP. Gotta give them a shoutout whenever possible). My car is stock weight. I'm comfortable in any intermediate group on slow tracks with LOTS of braking and on fast tracks with lots of cooling time but hard braking zones (road america for example). 30 min sessions always. I have never had brake fade. Never had bad pedal feel. Never wished my brakes were better. Never had a complaint honestly. That being said, I have not driven with a true BBK. I keep looking for a reason to switch over, but my current setup doesn't seem to have flaws. Could I be braking later? Am I simply missing out on pedal feel?

Am I missing something? Or am I just too slow?

A (good) big brake kit means seals last longer, pad swaps are stupidly faster (calipers don't come off), pads last longer (number of sessions), rotors last longer, is lighter than stock (rotating and unsprung mass), and has pedal feel/feedback is better. The stock brakes with track pads and track fluids are sufficient to not fade.... but there's still a ton of room for improvement.

PS4S. Although, I’m at their limits. They are what’s holding me back from going faster right now.

... and you're not pushing the brakes very hard if you're still on street tires. Street tires start melting long before you reach the limits of the stock calipers.

[Arith2]

... and you're not pushing the brakes very hard if you're still on street tires. Street tires start melting long before you reach the limits of the stock calipers.

I reached the limit of stock brakes on the street. It was a scary day when I did. Brake fade is scary when you need to stop for a stop sign. I decided 996 calipers were a must.

[Obioban]

I reached the limit of stock brakes on the street. It was a scary day when I did. Brake fade is scary when you need to stop for a stop sign. I decided 996 calipers were a must.

It's actually a lot easier to reach the heat capacity of the stock brakes on the street than it is on track. Track pads have an incredible amount of additional heat capacity.

That said, for sure one of the benefit of a good BBK is not fading on the street (running street pads).

[SteelGreyM]

I reached the limit of stock brakes on the street. It was a scary day when I did. Brake fade is scary when you need to stop for a stop sign. I decided 996 calipers were a must.

It's actually a lot easier to reach the heat capacity of the stock brakes on the street than it is on track. Track pads have an incredible amount of additional heat capacity.

That said, for sure one of the benefit of a good BBK is not fading on the street (running street pads).

How hard are you guys going on the street! I've never experienced this issue either.

Thanks Ian for the write up. I'm going to pick up some track tires before next season for sure. Found a very lightly used set of r888r's for a steal just yesterday actually. I figured my brakes would heat up way more with the extra grip. Pedal feel is great and all but i'm not gonna spend the cash until my braking performance suffers (which very well could be on the next track day with these tires). Until then, stockers!

[r4dr]

Have you considered doing 200TW street tires (Hankook RS4, Dunlop Star Specs, etc.) before stepping up all the way to R-comps?

[Arith2]

It's actually a lot easier to reach the heat capacity of the stock brakes on the street than it is on track. Track pads have an incredible amount of additional heat capacity.

That said, for sure one of the benefit of a good BBK is not fading on the street (running street pads).

Yeah, it makes sense because on the track there are cooldown laps to guage how long they should cool. 150 isn't achievable on most tracks either. It quite easy on quality roads with no one around. Mix that with Textars and you have a disaster waiting to happen. OE pads are a different compound but still crappy. Porsche pads are pretty darn good versus the BMW pads. After watching to footage of my dad taking his 987 to the Tail of the Dragon, I was sold on OE Porsche pads. They did hard driving for hours and he kept up with 911s. Basically the same calipers and specs.

[r4dr]

987s are also sub-3000 lbs. That plus being mid-engined and coming from the factory with some ducting (I assume it's similar to the 997 from the factory) helps a lot.

Repeated 150-0 stops will fade any brake system. I'd expect a quality stock E46 M3 setup would be fine in the Tail.

[Obioban]

Yeah, it makes sense because on the track there are cooldown laps to guage how long they should cool. 150 isn't achievable on most tracks either. It quite easy on quality roads with no one around. Mix that with Textars and you have a disaster waiting to happen. OE pads are a different compound but still crappy. Porsche pads are pretty darn good versus the BMW pads. After watching to footage of my dad taking his 987 to the Tail of the Dragon, I was sold on OE Porsche pads. They did hard driving for hours and he kept up with 911s. Basically the same calipers and specs.

The reason it's hard to fade the brakes on track is track pads. You can't come anywhere near the heat input into the brake system on the street that you can on track, with any level of reckless driving. Tracking is half hour long blocks where 80% of the time you're either WOT or braking near the limit of your tires (the other 20% being cornering at the limit of the tires). Even an M3 running high end 380mm rotors with 8 piston calipers and high performance street pads would have brake fade with a quick driver-- the heat generated is far in excess of any type of street brake heat. But, track pads are terrible street pads, so the limits of a street brake system will always be lower.

IIRC the OE 996 pad is also Textar.

[SteelGreyM]

Have you considered doing 200TW street tires (Hankook RS4, Dunlop Star Specs, etc.) before stepping up all the way to R-comps?

Yes. But someone in my area is selling a square 275/35/18 r888r with only half a mm of tread wear for $550. They’re not old either. So I think these are worth it.

[liam821]

It's actually a lot easier to reach the heat capacity of the stock brakes on the street than it is on track. Track pads have an incredible amount of additional heat capacity.

That said, for sure one of the benefit of a good BBK is not fading on the street (running street pads).

Totally this. The whole not fading running street pads is where a good set of BBKs come into play. I run cheap Centric Psoi Quiet pads, they're not the best pads in the world, but they're great on the street. They don't make much dust, they don't squeak, and they work fine cold. And still, they have plenty of stopping power on any type of street driving.

[S14]

PS4S. Although, I’m at their limits. They are what’s holding me back from going faster right now.

P4S is a great street tire that is capable of not comitting suicide while on track. But a proper tire will overwhelm the stock pads in a hurry. I bet if you utilize the R888R referenced above properly, you'll start to see the limitations of the stock brakes (even with track pads). I still hold true that 99% of M3 drivers don't need upgraded brakes (upgraded pads/lines/fluids is all you need), but when you start maximizing R-comps, everything changes. When you add aero, everything changes again.

[Davidyvr]

Hello! liam821,

After reading your post, I found that I have a similar calipers as yours and was wondering could you share your Fusion360 files to me to make an adapter for my e46 m3?
I am new here and searching many area and found you post is very helpful to me, thank you for sharing.

Merry Christmas!

I remember reading that thread. I think the brake bais was pretty off for the 18Z calipers - although they look massive on our cars. If you want a giant caliper, you're better off using Audi B7 RS4/1st gen R8 / Lamborgini Gallardo which are 8-piston monsters. I have a set I was going to use on my Audi S3 but since sold that car - if anybody is interested PM me I've been meaning to sell them. I looked into using them on my e46m3 with OE e92m3 360mm rotors, the brake bias isn't awful, but the company that made an adapter went out of business. I went so far as to design my own bracket in Fusion360 and 3d printed to verify fitment using an old rotor off my e93m3 and it all bolted up and looked pretty good. I ended up not going that route because those rotors are heavy AF, the pads are super expensive (you need 4 pads per caliper), and the e92m3 rotors are only 30mm which is a bit on the thin side for those calipers - they work but Brembo's spec calls for a 34mm rotor. I thought about using Brembo 380mm rotors/hats but they're so expensive and it was getting pretty heavy front brake bias with those massive rotors.

Plus, as I said earlier, I also think the Aston Martin DB9/V8 Vantage/Audi 8P RS3 (flipped) setup is the way to go on our cars - they're affordable, look great, good brake bias and pads are cheap and easy to find.

I did take a few pictures when I was test fitting the Audi/Lambo calipers though... enjoy If anybody wants the Fusion360 files just hit me up.





The billet ones are caliper adapters for an Audi/VW 8V MBQ


e92m3 rotors, 3d printed adapters, and Audi B7 RS4 calipers




Using a 12mm spacer






Caliper dimensions

[OPS]

"I remember reading that thread. I think the brake bias was pretty off for the 18Z calipers"

Actually it was the 17Z which was bad for our cars. The 18Z paired with the 996 rears were spot on.