M3 single piston caliper brakes, 135i multi piston calipers

[ruff]

This is BMW's press release for the 135i:

M-inspired performance for the 135i Coupe

The 135i Coupe offers more performance and a striking look thanks to M-inspired components. Features include an Aero kit for additional downforce at speed, better brake cooling and enhanced aesthetics while the Sports Suspension offers higher traction and reduced body roll with 18-inch wheels and performance tires. The Sports Suspension also includes with a high-performance brake system incorporating six-piston fixed calipers on the front and two-piston fixed calipers at the rear.

Isn't this ironic? Maybe the 135i will inspire the the M division. I know the M3 will have excellent stopping distances. However, IMO stopping distances are vastly overated and don't mean much on the track when brake fade sets in with the 3600 lb M3 misile after a few laps, due to a lack of multi piston calipers to better distribute the heat. The true test of brakes is if they remain fade free even when punished lap after lap ala Porsche and maybe even the 135i.

[Robert]

They have been testing the M3 on the ring for quite awhile. I really don't think they will overlook brake fade.

[Venky]

This topic has been beaten to death on Bimmerfest. I will definitely wait for reviews and will pull the tirgger only after I test drive myself. If not an E46 M3 ZCP seems much better option to me.

[swamp2]

Originally Posted by ruff

M-inspired performance for the 135i Coupe

The 135i Coupe offers more performance and a striking look thanks to M-inspired components. Features include an Aero kit for additional downforce at speed, better brake cooling and enhanced aesthetics while the Sports Suspension offers higher traction and reduced body roll with 18-inch wheels and performance tires. The Sports Suspension also includes with a high-performance brake system incorporating six-piston fixed calipers on the front and two-piston fixed calipers at the rear.

Isn't this ironic? Maybe 135 will inspire the the M division. I know the M3 will have excellent stopping distances. However, IMO stopping distances are vastly overated and don't mean much on the track when brake fade sets in with the 3600 lb misile M3 after a few laps, due to a lack of multi piston calipers to better distribute the heat. The true test of brakes is if they remain fade free even when punished lap after lap ala Porsche and maybe even the 135i.

Multi-piston brakes are a bit overhyped. I totally agree that BMW has had some models with sub-par brakes in the past (although my E36 with euro rotors, stock pads and stainless lines will take massive abuse with no problems). The real issue is cooling and secondarily brake rotor mass and diameter, last brake caliper mass. You need the diameter for torque, the masses for themal "mass" and the cooling is the real key. Multi-piston units are more important for aircraft setups where the calipers are 360 degrees all around the entire rotor. I have heard good and bad thus far about the M3 brakes, I think the jury is still out. However, the front end does look like it can route some serious air flow to the front brakes.

I also don't think stopping distance is overrated. It depends to some extent on the track: a 100km/h - 0 stopping distance is oubviously more important in something like auto-X as opposed to real track work. Braking distance says some important things about your chassis, suspension, tires and brakes! Stopping distance obviously means squat though if you have a fade problem.

All that being said I can't say I would not like giant multi-piston calipers on the M3, but if the brakes perform that is clearly much more important than their looks.

[ruff]

Swamp,
Why do you think the 135i is going with multi piston?

[swamp2]

Originally Posted by ruff

Swamp,
Why do you think the 135i is going with multi piston?

Because it is really lightweight and slower than the M3

[ruff]

Originally Posted by swamp2

Because it is really lightweight and slower than the M3

Being that you are one of the higher ups in the M division, I guess I should expect the company response.

[swamp2]

Originally Posted by ruff

Being that you are one of the higher ups in the M division, I guess I should expect the company response.

Come on, stop it with that

Really I don't know why, may be a bit for performance and may be a bit to "keep up with the Jones' ".

[Steved]

Originally Posted by ruff

Swamp,
Why do you think the 135i is going with multi piston?

Seen this, and they were Brembo calipers. I was surprised and wondered if this implied BMW would change the M3 to a fixed (rather than sliding) caliper, but they didn't.

Here is a picture of the M3's from our test in Marbella

[The CSL]

Great picture, Steved.

[LandShark]

the braking performance is NOT depends on how many piston a caliper has! also, the stock BMW brakes, even tho isn't the best, but they are not bad at all!! just give it a good set of race pads, and you will be fine!! don't believe me? see a pic that a track side photographer took a couple years ago for me. pay attention to the front disc!! it's 100% non photoshop'ed btw!!



I was just running euro rotor w/ a set of Hawks HT-10, and all day long I have no problem w/ the brakes at the track!

well, I must confessed at the end, I did eventually swap to a set of brembos tho. but main reason is b/c I got it at a very good price!

[ward]

I love people who think the only factor in brake performance is the number of pistons in the caliper

[ruff]

Originally Posted by ward

I love people who think the only factor in brake performance is the number of pistons in the caliper

Oh ya, I forget, you are pleased the M division went with the single pots. Now you can enjoy the essence and aroma of your scorched premium track pads, sitting behind the wall of the track, while underpowered Cayman's and the like fly by lap after lap on standard brakes. It's simple physics, multi pots distribute heat better and more evenly than single pots. But you don't believe this because you know BMW has better brakes than Porsche as evidenced by their superior braking performance at the track, right?

[///Murdock]

those brakes look beasty as FVCK! screw all the haters... u guys r noobs

[swamp2]

Originally Posted by ruff

Oh ya, I forget, you are pleased the M division went with the single pots. Now you can enjoy the essence and aroma of your scorched premium track pads, sitting behind the wall of the track, while underpowered Cayman's and the like fly by lap after lap on standard brakes. It's simple physics, multi pots distribute heat better and more evenly than single pots. But you don't believe this because you know BMW has better brakes than Porsche as evidenced by their superior braking performance at the track, right?

You do have a point multi-piston units can have more surface area mating the heat generation zones with the brake fluid. Hoewever this is mitigated if the single piston deisgn uses large pistons and I have seen some very small multi-piston design brakes. So until one measures the piston area and compares this is an advantage "on paper".

Also your post is very presumptive that the new car WILL have MASSIVE brake problems. ASS U ME...

I never stated nor argued that BMWs have better brakes than P-cars, nor did I say they would outperform at a track, period. P ceramic systems are quite phenomenal on all fonts, performance hot and cold, fade, wear and even cosmetic isues such as looks and brake dust. I only pointed out that thus far some stopping distances are superior for the M3 and for a much heavier car this is significant.

BTW which part of this did you miss

Originally Posted by swamp2

I can't say I would not like giant multi-piston calipers on the M3

Cheers.

[ruff]

Originally Posted by swamp2

You do have a point multi-piston units can have more surface area mating the heat generation zones with the brake fluid. Hoewever this is mitigated if the single piston deisgn uses large pistons and I have seen some very small multi-piston design brakes. So until one measures the piston area and compares this is an advantage "on paper".

Also your post is very presumptive that the new car WILL have MASSIVE brake problems. ASS U ME...

I never stated nor argued that BMWs have better brakes than P-cars, nor did I say they would outperform at a track, period. P ceramic systems are quite phenomenal on all fonts, performance hot and cold, fade, wear and even cosmetic isues such as looks and brake dust. I only pointed out that thus far some stopping distances are superior for the M3 and for a much heavier car this is significant.

BTW which part of this did you miss

Cheers.

Swamp, I was only responding to Ward's delightful comments with some over zealous statements to try and make a point with him.

[swamp2]

Originally Posted by ruff

Swamp, I was only responding to Ward's delightful comments with some over zealous statements to try and make a point with him.

Ugh, my bad. I thought your reply was quoting me for some reason. Blurry eyes from some good tequila last night maybe... na, just careless misreading. Sorry about that.

[ruff]

Originally Posted by swamp2

Ugh, my bad. I thought your reply was quoting me for some reason. Blurry eyes from some good tequila last night maybe... na, just careless misreading. Sorry about that.

All good, just keep up the good work on developing that new DCT tranny.

[southlight]

Originally Posted by ruff

All good, just keep up the good work on developing that new DCT tranny.

Did I miss anything here?
Swamp never told us that he's got a new job!?

Best regards, south

[swamp2]

Originally Posted by southlight

Did I miss anything here?
Swamp never told us that he's got a new job!?

Best regards, south

Come on you guys are cracking me up! I have done a bit of engineering in my time, even disc brake design and testing (for mountain bikes...but it was the first cable actuated hydraulic one) but you are going to have to stop with these silly statements.

I can't quite tell if they complimentary or insulting or a bit of both...

[southlight]

Originally Posted by swamp2

Come on you guys are cracking me up! I have done a bit of engineering in my time, even disc brake design and testing (for mountain bikes...but it was the first cable actuated hydraulic one) but you are going to have to stop with these silly statements.

I can't quite tell if it they complimentary or insulting or a bit of both...

[lucid]

Originally Posted by swamp2

Come on you guys are cracking me up! I have done a bit of engineering in my time, even disc brake design and testing (for mountain bikes...but it was the first cable actuated hydraulic one) but you are going to have to stop with these silly statements.

I can't quite tell if it they complimentary or insulting or a bit of both...

Take it as a compliment: you take the time to understand what BMW is trying to do with the E92 M3, and do a pretty good job in getting that across. Nothing wrong with that!