pocholin

Come on you guys, this person needs at least one excuse to upgrade to AMG brakes, give him one for God sake!

He has mentioned he needs new rotors so why not the AMGs, phattbam just do it! Your car will thank you for it. IT WILL LOOK BETTER for the little extra you have to spend since you need to replace old ones anyway.

preyx

Does the AMG brake kit come with red calipers? I am led to assume so.

pocholin

I don't think so, C32 calipers are grey, but really good looking.

Mach430

The easiest way to find out how the C32 brakes feel would be to get in a C32 and brake! The C32 probably has the best brake feel of all stock Mercedes. Just as the CLK55 out brakes the CLK430, the C32 out brakes other C's. You will notice a difference with upgraded brakes.

phattbam

thanks, i'm gonna go with that, it is an enhancement in performance, i plan to do more to the engine as the warranty winds down. it will fill up the gaps between the brakes i have now and the wheels i have on it. yes i should have waited for the c32 but where would the fun be???? thanks for all your support and sorry for any problems this caused....

JustinTRW

There's no question the C32 brakes will be an upgrade to the C320. Using your "brake lock-up" argument, some of you are saying that on the same tires, both brakes perform equally at the threshold of lockup (avoided by ABS). However, the C32 brakes will reach this threshold faster (if at all), in which case maximum braking force is achieved for a longer duration. This has little to do with brake pedal force, I'm talking about the tire/brake relationship. This is how I see it, explain to me how I am wrong.


BTW, it's not the rotors that need heat to operate, it's the pad. Certain racing pads do not work worth a dime on the street because of low heat.

JustinTRW

That's not what I thought. Larger rotors provide a) more braking surface area, and b) better mechanism to dissipate heat. Perhaps you are thinking about the both the extra weight and the extra heat needed for racing pads.

mdp c230k

Yes, C32 brakes can grab the rotor harder than stock C brakes, so what? If I stomp on my C230K brakes they will imediately try to lock which means the force they deliver is more than needed to stop the car and it is reached just as fast as the C32 calipers. i.e. If two weight lifters both lifted 100lbs but one could max at 200 and the other at 300, which one lifted 100lbs better? Neither, as both were well within their limits. Consider stopping as the 100lbs weight and the two lifters as stock brakes vs C32. Maximum force from the brakes is available almost instantly. Remember that more force is worthless if it causes lock up, it can't be used.
You are correct about the pads. They heat and become more 'sticky'.

pocholin

All this discusion about the C32 brake system and C320 brake system is indicating that it doesn't make a difference which one you put and it even indicates that the C320 brake system brakes quicker. If this is tru, why in the world MB engineers decided to put those brakes on the C32? Why not just keep the same brake system on the C320? There most be some benefits to the C32 brake system so that it self is called an upgraded system.

DtS

Becuase the C32 comes factory equipped with 17-inchers where the C320 comes with 16-inchers. And because the C32 is made for doing good on a race-track for a long period of time (where brake-fading might occur) whereas the C320 is made for autobahn-cruising at 240 km/h, where you need to brake real hard every 5th minute and not every 5th second as on a race track

Drew_ML

With all due respect, that's nonsense. It is you that seems to be labouring under some misapprehension. For example, for '00, increased the brake size (i.e. rotor and caliper/pad size) for the ML430. Everything else, tires, wheels, etc. were exactly the same. In measured tests, the '00 ML430 had a shorter stopping distance than the '99 ML430, and even a bit less the ML320. Prior to the brake size increment, the '99 ML430 had stopping distances a little longer than the 320, due to the extra weight.

In Hotrod TV, the guys changed a stock Camaro's brakes to a much larger Baer kit. Everything else was untouched. The result was about 10-20 feet shorter stopping distances.

The distance from the centre of the rotor to its edge (radius) can be thought of as a lever and the caliper in effect pulls on the lever to slow the vehicle. The bigger the rotor, the longer the lever. The longer the lever the more effective the caliper. It is easy to understand then that larger rotors increase braking capacity.

I do agree that C-class's brakes are more than adequate for street use though, and even some track use (based on personal experience with the C320 on a track).

Class C

Nicely put Drew_ML,

After doing some research in this subject, I came out with the same thoughts.

JustinTRW

See, this is where I disagree. If ABS was disabled, I don't think the C320 would reach WHEEL lockup as quickly as a C320 with C32 brakes.

Actually, using your analogy against you, there are a few weakpoints. First, wheels do not lock as quickly as you believe. In addition when driving for sport, you don't stomp on the brakes anyway. Smoothness is key. Therefore, a lifter who maxes at 300 can indeed lift 100 better than someone who maxes at 200. Why? Consider that it is HARDER for the weaker lifter to perform the same task. They both get the job done (both brakes stop the car), however the better lifter will be able to do it faster. Let's say to get a stopping distance of 115 ft. 60-0, they must lift 175 lbs (because stopping that short is hard for the C320). The weaker lifter will most likely a) take longer, b) struggle after more reps. Basically what I'm saying is, that if both cars do one 60-0 test they might be similar. What about on the second run? I bet the gap grows. Does this matter? Yes.


Drew_ML's post demostrates what I'm talking about. Yes, at some point better tires will be needed before any gains are realized. However, saying that C32 brakes will not result in ANY gain I don't feel is correct. Another issue is heat. Someone on this board put C32 split-spoke wheels on their car and guess what? They were dead hot after every spin around town. The brakes were transfering heat like crazy to the wheel. I can go drive my car hard and the wheels will be fine. This is another issue, not entirely relevant to this discussion.

Good thread.

vadim

No arguing about that. Whether this will provide shorter stopping distances, is another question. It would *if* tires would never lose traction (lock up). If the breaks are capable of locking the wheels up, there's no need to increase this leverage. That's what's being discussed here, don't miss the point, please re-read the thread.

German cars are built to be driven fast. In Germany there are no speed limits on autobahns. If you are doing 240 km/h, having good brakes is absolutely vital. This is one of the areas where I'd trust their engineers at 100%.

vadim

It does - to some. Doesn't to many, as DtS mentioned - a C32 driver is likely to need to use the breaks more frequently compared to a C320 driver.
This essentially says that the brakes of that person's car are better, as they are more efficient in heat dissipation, whereas yours trap the heat inside. Thinking that yours don't get hot is wrong, as the kinetic energy of a moving car needs to be converted into some other form for the car to stop. And that "other" form is heat - basic physics.

SoCal240/6

Yes, larger rotors can increase braking *capacity*. But when you are talking about minimum stopping distances, once the brakes are capable of activating ABS, NOTHING FURTHER CAN BE ACHIEVED BY LARGER BRAKES. The laws of physics just cannot be altered.

On a Camaro, it may be different, depending on what kind of ABS system the car has, how the brakes are balanced, etc. On a C320, bigger brakes can't help because it has a 4 channel ABS system where each wheel is independently brought to the treshold of lockup.

On the ML, you are talking about tests on different year vehicles, at different times, under different conditions, with possibly other small changes made to the vehicle.

Physics is physics, once ABS is activated the limiting factor is not the brakes, but traction. Bigger brakes do nothing to give more traction.

Justin, yes, after repeated 60-0 runs, distances will increase. But probably not after the first few runs, at least on an MB, which has a very strong braking system. Maybe after 5 or 6, very hard, back to back 60-0 runs, could some fade be induced. And even that is a maybe. But, umm, how often is someone going to do that on a street car? (or even a race car?). Never. No one is EVER going to drive a C320 hard enough on the street to get brake fade. Ever.

Finally, MB brakes are so power-boosted that anyone, no matter how weak legged, can easily get full braking power. Plus, if we are talking panic stops, there is Brake Assist, which will ensure full power.

FrankW

i don't know much about brakes and stuff, but i do know that ABS is not meant to stop the car faster. ABS originally was meant to let the driver to have the ability to control the car under very hard braking so that the car would not lose control and skid into the car ahead.

as for bigger brakes, i think in some cases they do help the cars to achieve shorter braking distance. the 99 and 00 ML430 have the same set up other than the brakes.

bigger tires will be another factor that can make the car stop faster.

easier solution...just get a C320 stock brakes with 17 tires to compare with a C320 w/ AMG or else bigger brakes with the same tire set up.

JustinTRW

No no, you're missing the point (if there was one) of what I was saying. On that car, the heat had no where to go so it transferred into the wheels. Of course my brakes get hot!!! They can handle it though. What I was saying is that my brakes could deal with the heat and transfer them in othe ways, rather that sending it all to the wheel.



Anyway...I think we can all agree with the differences between what the C320 and C32 brakes do. The only issue that needs clarification really, is whether or not the C32 brakes can reach the threshold of lockup faster or not. I do not think either car would lockup without ABS immediately.

avlis

Maybe I'm repeating some of the points described above, but here are my thoughts anyway:

I believe SoCal's explaination of the limiting factor in short stopping distances is traction (or lack of). Perhaps the idea behind upgrading to bigger brakes was not to achieve shorter stopping distances. The idea was to achieve more efficient slowing of the vehicle. I would believe that there are less mechanical stresses on larger brake componants and therefore larger barkes are more efficient at repeatedly slowing the vehicle (not just stopping it in a short distance).

I don't know whether or not the MB brakes are "over-designed" so I won't argue that point, but I believe that a lot of the "hype" over bigger brakes is simply phsycological. Even if larger Brembos are not necessary, I'm sure MB/AMG would get some negative press if they didn't provide "high-performace" brakes to go along with their performance cars.

Side note: I've heard that F1 cars are limited to a small wheel size in order to keep brake rotor sizes small which, in turn, was supposed to keep speeds down.

Drew_ML

Once again, this is untrue. We're not altering the laws of physics at all. You're talking as if ABS is a bad thing. If you've taken any sort of decent advanced driving course (which you don't seem to have done), you would've been told that ABS is one of the best innovations that has been invented, not only for street, but for track use as well. It allows the driver to leave the braking till the last minute, and yet be able to brake hard without worrying about lockup before making the transition from brake-to-throttle on the track. This is a very significant advantage when it is raining during the race and track is wet, and why it is banned a lot of situations (or they may have a choice between an upgraded braking system, or a stock brake system and ABS; not both).

Wheel lockup occurs when the front brakes start slowing down the front tires before load transfer can help to delivery the extra grip. This is why stomping on the brakes on a non-ABS equipped vehicle is not a good idea. When the resistance to the tire's rotation is greater than the force acting to revolve the tire, and the tire will stop rotating.

A locked tire has 30% less traction than a rotating tire at the threshold of lockup. ABS keeps the tire at the threshold of lockup. The notion that it increases stopping distances is only partially true. ABS (at least a decent system) may increase stopping distances in situations such as very deep snow or gravel, where locked front wheels will dig in and create a ridge of material in front of them
hence helping to slow the vehicle down. In just about any other situation, ABS is beneficial.



So what you're saying is that because the C-class has 4 channel ABS, it can't benefit from larger brakes? That's ludicrous! Larger pads/calipers/rotors means that there is more friction. In case you've forgotten, when the pads rub against the brake rotor when the brakes are applied, creating friction which slows the car down. The more friction, the faster the vehicle will slow down.

Because there is more friction, one does not have to apply as much pedal pressure to slow down the vehicle as before a brake swap. This is why other posters here have noted that some adjustment is required as far as their braking effort is concerned.

All street vehicles have some sort of similar guestimate brake porportioning done by the designers of the cars. The bias is figured on a particular loading and target range of deceleration.

You may want to research this before making assumptions. For 2000, the ML430 gained about 150 lbs of weight over the 1999 model. Other than that, it had the same wheels, same tires, same ABS/ESP system. Despite the weight gain, stopping distances decreased after the larger brakes were fitted to it.



So what you're saying is that if I halved the brakes of the stock C-class's size but I'm running on slicks, I'll be able to stop just as fast, or faster? Hmm, think about that....if you want to elaborate more on this, go right ahead



I agree...partially. I wouldn't use "ever" since there may be the person who runs down a mountain pass riding on the brakes without using engine braking. Obviously you would probably get brake fade in that situation.:o

vadim

Transfer what? Where?

TimmyC230boy

ok dude, if you wanna spend your money on brakes then go right ahead and do it. sure you might stop shorter, assuming you dont enforce ABS, but couldnt you just always hit the stock brakes a little harder? But once ABS is going it doesnt matter if you have 18 inch rotors and 8 piston calipers, ABD will only allow o much presure on the rotor. If you upgrade your brakes you owe it to yourself to upgrade to wider tires too.

Myself I'm looking into a set of drilled rotors. I live on a "mountain" and we have alot of speed bumps, not the little speed humps you can do 15mph over. you have to almot completely stop to go over them. I try to engine brake as much as possible but i still end up haveing to hit the brakes pretty hard none the less. Which over 14K miles has caused my rotors to warp a little and cause them to squel when the brakes are used more than 50%. With crossdrilled or slotted rotors you greatly reduce the amount of heat that is produced by the rotor. I had 15 inch crossdilled rotors onmy camaro, along with Corvette calipers. they were awesome. I remember the calipers were a mix of titanium and something else. The titanium had a very high heat transfer rate, meaning, that 3-5 minutes after hard driving the rotors were cool to the touch, no to mention they look really nice. I don't think upgrading to crossdrilled or slotted rotors are ricey at all.

vadim

Timmy, take a look at this first...

TimmyC230boy

Yup that is a pictures of the Brabus brakes that the winner of the cannonball/gumball europen run used. Thats not anything a normal car would be put through.

JustinTRW

Instead of transfering the heat from the rotor to the wheels, it is also lost to the surrounding environment (air). Do an experiment and heat an iron pot on your stove. Then turn off the stove and let it sit. See what happens.


TimmyC230boy: Are you kidding me!!!! The issue that you have not even attempted to respond to is when ABS intervention occurs. Do you believe the smaller brakes will reach this threshold earlier than more effective ones? Besides, by self admission, you say that you have warped your brakes. Now you cannot really argue about the added benefits of a better braking systems. Notice that I'm am not saying phattbam should get this AMG system (cost vs. improvement to him is iffy). I would start with motul brake fluid and better pads...


Re: Vadim's pic. I bet you they were miscared for. That's not going to happen to me.