Anyone running Z17 or Z18 Brembo BBK Kit? Thoughts?

[mrgizmo04]

According to BuildJournal, the DB9 has 40/44 piston size with the larger trailing.

Never thought about pad tapering before, but very insightful. Thanks!

Buildjournal has some of the older options, yes. Ok, DB9 has different pistons. YAY!

I tie out to their bias calculations +/- 0.1%. DB9 places more bias forward and important point I forgot to mention in my previous long post, although I alluded to it with "understeer", is that most folks like CSL or other staggered wheels and placing more forward bias on skinny front tires will overload them further, resulting in plowing.

I will not comment on Buildjournal in general, they are selling "stuff", but it is scary to me that they crown Megane calipers as "best" upgrade. I guess it depends, best for what. Their primary point is bias. Ok good start.

I want to make sure folks understand tapering pad and what that results in from same size pistons. Leading piston effectively overpowers the trailing piston because the trailing piston gets additional gases/material to overcome, which it can't. The leading half (approx) of the pad starts wearing faster, tapering the pad. That starts placing the pad in the caliper at an angle and jamming it in the caliper because it no longer sits square. From a piston point of view, the backing plate also starts putting pressure on a single point of the piston instead of sitting flush against the circumference face of the piston. This also jams the pistons in their bores. The net result of this is you have a jammed piston and pad when you need your brakes. It is somewhat similar to pad knockback, yet very different, as pad knockback has several solutions like pumping the brakes a few times or adding piston springs. This tapering becomes scary as it changes the geometry and you basically experience jammed brakes.

Again, can be mostly disregarded if street driving.

Sent from my SM-G950U using Tapatalk

[mrgizmo04]

This is a super interesting topic. According to the Build Journal page I link below, several combinations of 4-pot front calipers move the bias slightly rearward.

For my purposes, I’m getting close to the wear sensor on my current stock brakes. Increased thermal capacity and a potentially lighter caliper are what make an upgrade tempting. I would be lying if I said looks weren’t also a factor.

Sticking with floating calipers but going to the ZCP/CSL-size rotor (and bracket) would require new rear calipers to balance the bias, no? But then if I’m going to spend $600+ on rear ZCP calipers, a set of aluminum 4-pots up front now sounds like the smarter buy.

https://thebuildjournal.com/tech-gui...r-is-the-best/

Yes some setups move the bias rearward. Is that a setup that you want on YOUR car?

I usually go into TMI in my posts, but I'm just providing real world applications and engineering/physics of it. So if folks are learning, I'm happy.

First - what is your use for the car? Have you experienced brake fade necessitating more heat capacity? Pads close to the backing plate and worn rotors is as close as you can get to limits of current system's heat capacity. If not, my feeling is that there is some justification for needing an upgrade and sexy marketing language about "benefits" of upgrades like more thermal capacity, etc, is having it's intended impact . Remember, all these guys are trying to sell you products, whether you need them or not or whether they are the right ones for you.

On rear bias increasing and whether that is right for your driving style or your car - depends what you are doing with the car. In our cars it is very easy to get 150 lbs off the rear with battery, rear seats, stuff in trunk. Pair that with soft front suspension, your car will dive with featherlight rear and rear bias becomes scary. Again, that is more for performance driving and track. Maybe you are an advanced driver and for your car setup you want additional rear end rotation, 🤷♂️. Street driving it won't impact you that much.

Sent from my SM-G950U using Tapatalk

[Epsilon]

Using same piston sizes from trailing and leading on front of the car when performance driving is very suboptimal, as the pad starts tapering and you get poor pedal feel (proper sizing is to have larger piston trailing). I think same size piston is also the problem with Megane caliper (and maybe the DB9, although this specific one I don't remember). So some of these options are not meant for proper performance driving and track use.

According to BuildJournal, the DB9 has 40/44 piston size with the larger trailing.

Never thought about pad tapering before, but very insightful. Thanks!

[WestBankM4]

Just got the car back from the shop with the new brakes installed. Decided to paint them yellow at the last moment.

So the specs are:
- Front calipers off a w204 c63 amg
- 360mm rotors off a e9x m3
- Pads are ebc redstuff made for c63 amg.
- 15mm spacers at minimum to clear...I have maybe 2 or 3mm of clearance right now.
- Rear calipers off a 996
- csl rotors in the back


As you can see the sweep is very good. I maybe should have gone with the 380mm in the front but since i was doing 996 conversion in the back i thought the disparity in sizes would've been too drastic.

Honestly if the guy who previously posted that this was the worst retrofit in terms of pedal feel i would not have noticed anything....Feels almost stockish...if you twisted my arm i might say that the pedal travel is a bit further but when you get there it grips like hell. Overall very happy with the early impressions.

Can we see the rears as well? I want to see what a 360mm front rotor and 328mm rear rotor look like together.

[nahvkolaj]

This is a super interesting topic. According to the Build Journal page I link below, several combinations of 4-pot front calipers move the bias slightly rearward.

For my purposes, I’m getting close to the wear sensor on my current stock brakes. Increased thermal capacity and a potentially lighter caliper are what make an upgrade tempting. I would be lying if I said looks weren’t also a factor.

Sticking with floating calipers but going to the ZCP/CSL-size rotor (and bracket) would require new rear calipers to balance the bias, no? But then if I’m going to spend $600+ on rear ZCP calipers, a set of aluminum 4-pots up front now sounds like the smarter buy.

https://thebuildjournal.com/tech-guides/e46-m3-bbk-brake-bias-guide-why-the-megane-rs-trophy-r-is-the-best/

[mrgizmo04]

Food for thought. Most can ignore this post.

These options all look interesting until you start looking at the details. For anyone street driving, what I say can probably be disregarded. Let's all just accept that 99+% of the folks looking at 6pot, or other 4pot "upgrades" are doing it for looks. Nothing wrong with that.

I am semi happy with 996 kit for street and track. Read, this is where the bias and feel and power actually come into play, when you are hauling 130 mph down a straight and need to nail down a turn slowing down at the limit to around 45 mph to navigate a corner to stay on track and not eat gravel for lunch.

Can all these sellers make any caliper fit onto any rotor. Sure. Make a bracket with the right offset to center around whatever common size E46 rotor being used CSL 345x28 or e9x 360x30. Should we put those kits onto our cars. I'm not sure.

Most of these options will put brake bias to around or even over 70% (assuming paired with popular e46 rear options of stock/CSL/996). Does it matter for street driving? Not so much. In an emergency when you slam the brakes, you will stop, ABS/DSC will save you. For those trying to drive at the limit, that bias is not ideal as that affects all aspects of handling when working the car on entry, and makes a difference whether you stay on track or plow into a wall.

Most of these kits come from much heavier cars, and have to put out a lot of stopping power via 3x smaller pistons (6pot) or 2x larger (4pot), but where they are appropriately paired with their rear brakes on those cars. Putting these front only options on our cars makes them suboptimal.

Touareg option uses 2x 46mm pistons. That is a lot of volume to pump to front brakes. You will get longer pedal travel with our MC. As an example of more proper piston and power sizing, take ST40 kit which uses 42/38 pistons on 355 rotor, 996 uses 40/36 on 345 rotor (a bit underpowered on its own).

Using same piston sizes from trailing and leading on front of the car when performance driving is very suboptimal, as the pad starts tapering and you get poor pedal feel (proper sizing is to have larger piston trailing). I think same size piston is also the problem with Megane caliper (and maybe the DB9, although this specific one I don't remember). So some of these options are not meant for proper performance driving and track use.

ZL1 uses 38/34/30 pistons, AMG uses 38/36/34. Also more total volume of fluid, longer pedal travel and more clamping front bias around 70%. My rough calc is ZL1 69% bias and AMG is closer to 72%.

Another problem is that most of these calipers on these donor cars come with x32 or x34 or even x36 mm wide rotors. Can these sellers find the midpoint for how to fit calipers on E46 with the right mounting bracket/adapter? Sure, that's why they are selling it. They heard the forum/Facebook/Insta hype and craze of putting Brembros on E46, so they are filling the gap in the market. Do I want to run any of those options on a x28 CSL rotor or even a x30 E9x rotor. Probably not. I don't want to have the pistons protruding halfway out with brand new pads and then run the risk of popping them on track when my pads run to the backing plate. Unless these guys pair these kits with proper thickness pads (much thicker than comes on those donor cars), but I suspect they are not offering that . Most standard pads are 16-17mm thickness.

Just my $0.02.

Sent from my SM-G950U using Tapatalk

[crow4213]

Just got the car back from the shop with the new brakes installed. Decided to paint them yellow at the last moment.

So the specs are:
- Front calipers off a w204 c63 amg
- 360mm rotors off a e9x m3
- Pads are ebc redstuff made for c63 amg.
- 15mm spacers at minimum to clear...I have maybe 2 or 3mm of clearance right now.
- Rear calipers off a 996
- csl rotors in the back


As you can see the sweep is very good. I maybe should have gone with the 380mm in the front but since i was doing 996 conversion in the back i thought the disparity in sizes would've been too drastic.

Honestly if the guy who previously posted that this was the worst retrofit in terms of pedal feel i would not have noticed anything....Feels almost stockish...if you twisted my arm i might say that the pedal travel is a bit further but when you get there it grips like hell. Overall very happy with the early impressions.

[Lee_Enfield]

Interesting. Was not aware of these options. I was thinking of an f80 brake swap but maybe the cayenne kit is another option. Since everyone wants 2500cad for a set of junkyard f80 calipers, not including rotors, these might be a good option.

Seems they use there own rotors. Are these just third party rotors repackaged or are they actually made in house? How are they?

[crow4213]

Where did you order your kit from? Signature Werks says the C63 calipers are not an ideal option for the M3 based on their research (at least for E9X M3 and F8X M3/4). https://signaturewerks.us/blogs/tech...it-information

Freakyparts out of the UK. Honestly not sure how well they'll work. Will update you guys in a couple of days when i get the car back.

[crow4213]

That D977 pad has 66mm of swept area height, which is ~4-5mm more than the ZCP rotor has to offer... is the pad hanging over the edges?

No, not at all, seems to be perfect. Oh btw, i am using the 360mm rotor from the e9x m3.

[SWRT_M3]

I recently ordered the kit for c63 amg caliper swap. Fitment seems perfect but i had to shave a bit off the bracket for the pad I chose. Havent gotten the car back yet frol other work so idk if it works well, but it looks good.

Where did you order your kit from? Signature Werks says the C63 calipers are not an ideal option for the M3 based on their research (at least for E9X M3 and F8X M3/4). https://signaturewerks.us/blogs/tech...it-information

[GreyM340i]

Not bad $649 + $50 shipping to IL. Anyone have a opinion on these vs freakyparts BBK kit?

[Grke46m3]

I have been eying up signatureworks for a while now


Sent from my iPhone using Tapatalk Pro

[r4dr]

I recently ordered the kit for c63 amg caliper swap. Fitment seems perfect but i had to shave a bit off the bracket for the pad I chose. Havent gotten the car back yet frol other work so idk if it works well, but it looks good.

That D977 pad has 66mm of swept area height, which is ~4-5mm more than the ZCP rotor has to offer... is the pad hanging over the edges?

[crow4213]

I recently ordered the kit for c63 amg caliper swap. Fitment seems perfect but i had to shave a bit off the bracket for the pad I chose. Havent gotten the car back yet frol other work so idk if it works well, but it looks good.