Dr Chill

...take their car to Baer Brake Systems for them to develop a fitment for 2 piece rotors for our cars. The factory rotors are heavy and heat intolerant, aside from having poor lifespan. Also MB was so cheap they only ordered one rotor design rather than one for left and a mirror image for the right. One side actually channels air away from the disc surface. Nobody currently manufactures rotors that will be a factory replacement for our stock rotors, so if there is interest, Baer would probably make an application for us. Since the rotors on the E55, S55, SL55, and CL55 are the same, there will be a reasonable demand, I think.

Anyone want to help by bringing their car to Baer for measurement and fitment? They are in Phoenix, AZ.

For curiosity's sake, how many of you are definitely interested?

VelocitE55

I dont live in AZ and surely would not drive my car out there but I would be 100% on purchasing a set of multi-piece rotors for the car should they become available.

awiner

I would buy them too when I need replacements.

CynCarvin32

I would buy a set... question is are the rotors used by the factory also the same thickness as those used by the aftermarket company? I know this was tried for the C32 and the issue rested in the fact that the stock rotor was to thin and there was no racing rotor that would fit inside the OEM caliper. If all goes well it is simple but this could be a real issue.

With pads and rotors this car would stop just fine. The caliper is heavy but its more than strong enough for the job of slowing the car....even at the track.

Keep us posted Doc

deaguero

Dr. Chill: I live in the Phoenix area. I recently moved here about 4 months ago with my 2003 W211 E55 from So. Calif. I might be interested in helping if you could send me some details of what might be involved. I would like to help out if possible.

Dr Chill

This is still in the development phase, but it should be doable. I've been in contact with their sales mgr who is in the process of trying to get the okay from his boss to go ahead. It certainly would help if I can give him a name and number of someone willing to be a "guinea pig." I have no idea of the time required to accomplish this, bujt I bet there will be pretty good interest since these discs are far superior to the crap we have from the factory.

Regarding the thickness. The stock rotor is very thick-36mm while the aftermarket ones are usually 30 or 32mm. This shouldn't present a problem.

Beowulf

Dr Chill - I have a personal acquaintance in the Phoenix area that's _very_ tight with Baer. If deaguero is willing to be the donor car, perhaps something might be arranged. Let me know and I'll try to make contact with my connection.

Signal

craapp.. I just typed all these long detailed questions and the site ate them,...


grr...

anyways, Chill,

My questions were,

Why do you say the AMG brake rotors are inferior or not up to par? Is it because of the amount of time you can work them hard before they overheat? What are you comparing them too when thinking they are bad? Porsche, Corvette, etc? Isnt weight of vehicle a major factor there?


Also, If they indeed do not have unique rotors for pass side and drivers that does somewhat reduce venting efficiency, and would make me raise and eyebrow. Are you sure on this?

Lastly, what will make these newly designed rotors better then stock? How will you reduce weight without reducing thickness? What material will they be? Ceramic composite? Isnt that big $$$$?

Also, do you see the brake rotor problem as being there because you track your car or do you also see it as a problem with the car in general..

Thanks and much respect..

Dr Chill

Regarding the stock rotors, just look at the hole patterns. One side curves toward the front and the other away from the front. MB has only one part number for the rotor and not a left and a right. The disc is extremely thick and heavy and the pot is very heavy-since it is one piece, the two components are fused together. The center pot is just a huge heat sink that retains all the heat generated by the pig like mass of the vehicle. I'm not the only person whose rotors cracked all over from aggressive driving, and that's due to the heat buildup and retention.


The new 2 piece rotors should be able to withstand aggressive braking as seen in track events without cracking, provide better stopping ability, and last longer, aside from allowing better handling due to a decrease in the car's unsprung mass. They will be cast iron as well.

The last generation CLK55 had two piece designs with slots I believe. Our ****ty rotors simply are for show and MB focused on cheap because they believe in changing rotors whenever a brake job is done. They don't even measure rotor thickness when they tell you that new rotors are required.

Signal

Consider me interested...

Dr Chill

visit www.baer.com Their rotors come crossdrilled and slotted. The benefits include: elimination of pad outgassing, more aggressive initial bite, elimination of pad glazing, and improved wet weather performance. Lastly all rotors are zinc washed. Besides the visual appeal, this protective plating is a rust resistant finish.

awiner

Why does Baer need a entire vehicle ? Won't a simple rotor tell them all the need to know ?

Dr Chill

I believe they would make one sample rotor and confirm fitment before embarking on making more.

deaguero

Let me know who to talk to and when. I'll wait to hear from you.

adx

I game if these rotors are an improvement and compatible with the OEM rotors when it comes to servicing by the MB dealership. What about better biting brake pads that don't spew so much dust. BTW, I'm from Las Vegas would consider driving out to Phoenix.

Dr Chill

Phil, check your pm, I'd like to try to arrange Baer to check out your car.

Blocktrader

Chill, I am interested in 2piece rotors as well, but a few things to keep in mind while you pursue this. High mass in a rotor is typically a good thing for braking performance as it allows the rotor to store more energy while braking (the rotor cannot get rid of the heat as fast as it is being created during steady braking and therefore stores it causing the rotor to get hotter.) The high mass has the obvious negative affect on the car's handling though. The place where the MB rotors fall down are in venting the heat both during braking and after (obviously you know this first hand.) This is where you can get an improvement. You are going to have to find a compromise between the amount of mass needed to absorb the tremendous heat generated from stopping such a hevy car, keeping the mass low enough to help the handling, and venting good enough to get rid of the heat.

I would imagine Baer would want to test the car to find the balance of the issues I mentioned and that would explain needing the car. The rotors you pictured are the kind you usually see for the street applications. The "race" rotors are usually solid to prevent cracking. Were you clear with them that you were looking for a more extreme use application.

Two other routes worth pursuing as well. First, has anyone checked to see if the new "65" 2 piece rotors will fit the 55 cars. I looked at the SL 65 at Autohaus today and, while it was a brief look, the caliper looked the same. If that is the case it should be possible to have a new bracket done up cheaply.

The second route is to find a 2 piece brembo rotor (with the holes cast in the rotor as opposed to being drilled) that is very close in size and buy those. A machine shop could make new hats for these. Believe it or not, If you could find a good match in diameter, thickness and swept area, this could be the most cost effective option. Especially if there is a Porsche replacement.

Marcus Frost

Good thread, Dr. Chill. Two things I'd like to make a point on:

1.) Make sure the rotor is CAST with the holes, and NOT drilled with them. I cannot even count how many cars have cracked drilled rotors. No matter who manufactures them, brembo, etc.

2.) The fact that the rotors are all the same design (as in, the left and right rotors both are actually the same rotor, and one channels air away while the other channels it in) is probably their biggest flaw and I'm personally shocked MB did this. It's actually kind of embarassing.

-m

AMGfan

I'm in to Dr. Chill...

ima55r2

Lasy week I checked out the sl65 at lp evans and the same directional rotor is on both sides again! I thought they had bigger diameter rotors so wheel clearance might be an issue.

Dr Chill

Two comments. The mass at the disc center where the bolts hold the wheel-the hat, contributes less to stopping than mass at the rotor periphery. The billet aluminum hat will shed weight and heat better.

The SL65 rotors fit only under 19" wheels since they are larger diameter.

I will find out whether Baer Eradispeed Plus rotors have crossdrilled or cast holes.

Even if I could find a Brembo disc that would fit, finding a machine shop to make a hat that would work is not something I'd like to embark upon. Then there's the task of testing.