Brembo Caliper on stock rotor

[richardg]

Too be honest I don't want to spend 7k just to upgrade my brakes. I do love the look but I only track the car 2-3 times a year with the occasional auto-X.

[Z K]

Originally Posted by Malekreza11

I know. I am working on the caliper selection directly with Brembo. It's not going to be an off the shelf unit off a Porsche Cayenne or the likes.

However, a lot of the Brembo calipers are very similar to one another in this size range.

Sounds promising!

It's not the caliper size itself that is different... The pistons used in the calipers are sized appropriately for the car. I.e. the 6 piston caliper for their GT kit is the same for a number of cars but the pistons used in the calipers are car specific so it matches the stock fluid displacement and works with the factory brake master cylinder. Stoptech does the same thing in their application specific brake kits.

[Malek@MRF]

I will keep everyone posted on the progress of this project. However, please understand that it is not a simple task and we want to make sure we have it down right and ready.

Glad to see there are others interested in this!

Malek

[THE TECH]

Originally Posted by Malekreza11

I will keep everyone posted on the progress of this project. However, please understand that it is not a simple task and we want to make sure we have it down right and ready.

Glad to see there are others interested in this!

Malek

Are you thinking weeks? Months? Longer?

[JAJ]

Originally Posted by Z K

The other thing to look at is if the caliper displaces the same amount of fluid as the stock caliper. If you put a larger caliper on that needs more/less brake fluid, it changes the brake bias, throws off the ABS and overall isn't very good. So it has to be a E90 M3-specific caliper used - not a off the shelf part.

I don't think you mean the volume of brake fluid in the caliper, I think you mean caliper volume change per unit of line pressure. And even then you're not done because you also need the right combination of piston area and pad shape so that the brake torque per unit of line pressure also matches.

With all that said, though, a lot of what you need to know comes from folks like Brembo directly. And as Malekreza11 said, in that size range, the piston sizes tend to converge around some standard setups, and that includes the OEM calipers.

[tha_good_life]

this is awesome! Can't believe bmw didn't do this from the beginning.

[richardg]

so excited

[bigjae1976]

Originally Posted by richardg

I am willing to bet under street use they would last just as long and under track use I am ASSUME they would wear at the same rate. I know there are other factors but I am assuming the face of both the brembo and oem rotors is the same material. Also for the price of one set of brembo rotors you can get 2 sets of new OEM rotors.

I've used the floating E46 M3 rotors on my E46 which are of the same design and probably the same type of iron for the rotor disc on the E9X M3. They got a pretty bad lip when used with track pads pretty quickly. The biggest problem was the cracking around the holes.

Whereas my stoptech aero rotors have worn much better. My rotors have worn about 1mm after 2 very hot track weekends.

I'm guessing that most looking for a cosmetic upgrade will be happy with this. Not sure if this will be something for someone is looking for more heat capability in their brakes. That is an aspect of this great idea that is up for discussion.

[swamp2]

The weakest link in the OEM brake system is the pads. The performance difference between the OEM pads and factory BMW track pads have shown this. The rotors are OK, at least they float in some sense. However, their floating design also does a "wonderful" job of blocking a tremendous amount of air flow through the rotors vanes. Although perhaps not rigorously quantifiable I would say the next weakest link is either fluid or rotors. Calipers come in a much more distant placing...

How much money can you really save buying four new Brembo calipers as opposed to a kit with rotors? I would imagine kits have a built in discount of sorts that single calipers (pair or complete sets) would not have.

Last but not least - Malekreza11 be prepared for a ton of simulation, analysis, real engineering, testing, etc. No one wants to release a potentially flawed design for a cars brake system, probably its single most important safety system. Even though it really is just a block of metal with a few bolt holes in it, it is nothing to screw around with.

[JAJ]

swamp2 pretty much nailed it. Once you solve the pad problem, the next step is to get the rotor temps down. That means a heavy rotor with lots of vanes. The OEM brakes, even with real race pads, just can't cool as well as a BBK rotor:

http://www.m3post.com/forums/showthr...ighlight=rotor

[GTM_Challenge]

Originally Posted by richardg

I figured it was maybe the smaller caliper that brembo sells for their 365mm/345 setup.

Just FYI, the calipers for the Brembo GT kit, for 380/365 and 380/345 are the same calipers. Only different brackets, and rotors are used for the larger.

[richardg]

Originally Posted by GTM_Challenge

Just FYI, the calipers for the Brembo GT kit, for 380/365 and 380/345 are the same calipers. Only different brackets, and rotors are used for the larger.

OK.....the more you know

[FruitCake]

I thought chris from Brembo said that the caliper is the same for the 365 and 380 kits but the piston is not the same?
nevertheless, i remember Brembo did a caliper upgrade for the E46 M3 rear...but not for the front.

Im sure if it was effective to upgrade front only, Brembo would have done so.

Ill let the Formula1/MotoGP champion brake makers decide on what is safe on my car @.@

[Technic]

Originally Posted by FruitCake

I thought chris from Brembo said that the caliper is the same for the 365 and 380 kits but the piston is not the same?
nevertheless, i remember Brembo did a caliper upgrade for the E46 M3 rear...but not for the front.

Im sure if it was effective to upgrade front only, Brembo would have done so.

Ill let the Formula1/MotoGP champion brake makers decide on what is safe on my car @.@

That was a very nice kit for the E46 M3 rear rotors...

[Checkcaptain]

They fit with stock GTS rotors - just plug and play:

http://imageshack.us/photo/my-images/199/bild073er.jpg/

[aus]

Originally Posted by FruitCake

I thought chris from Brembo said that the caliper is the same for the 365 and 380 kits but the piston is not the same?
nevertheless, i remember Brembo did a caliper upgrade for the E46 M3 rear...but not for the front.

Im sure if it was effective to upgrade front only, Brembo would have done so.

Ill let the Formula1/MotoGP champion brake makers decide on what is safe on my car @.@

Brembo also knows that such a kit will KILL sales of their full BBK's since 98% are for looks only.

Originally Posted by Checkcaptain

They fit with stock GTS rotors - just plug and play:

http://imageshack.us/photo/my-images/199/bild073er.jpg/

Checkcaptain has some explaining to do!!!!!

.

[richardg]

what size are the rotors and what type are they on the GTS/CRT? They are probably different from what is on our standard car.

[Technic]

Originally Posted by Checkcaptain

They fit with stock GTS rotors - just plug and play:

http://imageshack.us/photo/my-images/199/bild073er.jpg/

The discussion here is about the M3 rotors, not about the completely different GTS rotors...

From the official GTS announcement:

The high-performance brake system featured on the BMW M3 GTS has been designed as a fixed-caliper construction and comprises six pistons on each of the front wheels and four pistons on each rear wheel. Compared to the BMW M3, the brake discs are 18 mm larger in diameter at the front and 30 mm larger in diameter at the rear. Furthermore, steel-armoured hoses are used.

Considering that the GTS calipers are really Brembo for OEM then it is obvious that non-OEM Brembos will fit. They are the exact same calipers.

[Technic]

Originally Posted by aus

Brembo also knows that suck a kit will KILL sales of their full BBK's since 98% are for looks only.

At the end of the day, I do not think that Brembo is much interested in the reason of the sale -looks or autocrossing, racing or whatever. They want to sell. Brembo did not have any problem creating that E46 rear caliper kit and it looks like they sold quite a few.

One thing is selling a $7000+ kit for the M3 and then another selling a $5000 kit. That $2000 could be the difference of making another sale or simply not otherwise.

[Checkcaptain]

The GTS fronts are 378x32 and the rears are 380x28.
The OEM GTS rotors are much lighter than the Brembos and the GTS rears have a SS insert for the E-brake where the Brembos only have the aluminium pots. I drove the GTS rotors now for about 25k kms also with heavy track use on Endless pads and they take it pretty well. i always would prefer them over the Brembos. Here are some more pics of my new rotors:

http://imageshack.us/g/151/p1100477q.jpg/

[tha_good_life]

Originally Posted by Checkcaptain

The GTS fronts are 378x32 and the rears are 380x28.
The OEM GTS rotors are much lighter than the Brembos and the GTS rears have a SS insert for the E-brake where the Brembos only have the aluminium pots. I drove the GTS rotors now for about 25k kms also with heavy track use on Endless pads and they take it pretty well. i always would prefer them over the Brembos. Here are some more pics of my new rotors:

http://imageshack.us/g/151/p1100477q.jpg/

[tlp]

Originally Posted by Checkcaptain

The GTS fronts are 378x32 and the rears are 380x28.
The OEM GTS rotors are much lighter than the Brembos and the GTS rears have a SS insert for the E-brake where the Brembos only have the aluminium pots. I drove the GTS rotors now for about 25k kms also with heavy track use on Endless pads and they take it pretty well. i always would prefer them over the Brembos. Here are some more pics of my new rotors:

http://imageshack.us/g/151/p1100477q.jpg/

Welcome back Ralf!!!