Carbon Ceramic v Steel brakes. Street use only.

on a more serious note......yes, you are correct.

you've brought a different perspective into it now. On a car like mine you can fit a set of big brakes and eliminate any brake issues...this is an irrefutable fact. We're not racing, and that sort of upgrade is more than adequate for very sprited driving...up hill or down.

However, you new and very clever point is that in cars with limited room for a brake upgrade, then yes, obviously, CCBs would be a great idea.

I've heard from a few sources that CCB discs have to be changed on an "age" basis more than a "wear" basis. Is there any truth in that, and, if so, how often?

 

hang on..just picked this up....can you repeat that, please, so we can have a bit more of a laugh at you?

a common misconception!!!!!! i expected better from you.

i'm talking about the weight comment, btw

 

Here's an interesting question.

The brake fade on my boxer was caused by the fluid boiling, not overheating of the pads.

what would CCBs offer to overcome that issue?

Maybe Phil's assertion about bolting on CCBs solving the brake issues of a boxer ( for example) is incorrect if the assumption is that CCBs working at higher temps would be a fix.

 

But the fluid overheats because the heat is sitting in the calipers, not transferring properly to the disks and surrounding air.

 

thank you, captain obvious....but would CCBs overcome that issue? There's almost no ventilation inside a boxer's wheel.

incidentally...finally a claim of shorter braking distances:-

http://www.systemst.com/flash/Steel-vs-Ceramic.swf

http://www.systemst.com/flash/Carbon-Carbon-vs-Ceramic.swf

 

Or its got the wrong/old fluid in it, or the car is being driven beyond its technical capabilities....

Would CCB fix these issues? Well if you fitted them, presumably the car would also receive a fluid flush, so that eliminates 2 possible problems with one replacement... thereby not allowing the finger to be pointed directly at either one....

 

the fluid was new and was castrol SRF.....PLEASE!!!!!!!!!!!!!!!

is it a caliper issue only, perhaps? maybe changing the caliper would have solved the problem. i remember reading about calipers with the fluid running externally or something???? I forget now. Like i said, though, it wasn't the overheating of the pads/discs that caused the fade.

 

Please don't bring that up. I've been trying to forget about that for a long time. AND my car has been trying to forget about that for a long time.

 

Was the SRF fresh, or had it sat on the shelf in the preparer's workshop for eons?? There is a difference... and was it just a top up/bleed or a proper full bleed flush?

Was the fluid perfectly clean when it bled out of the calipers? Or did it have gunk in it.

Are all the internals in the braking system clean and free of gunk, the rubbers inside the master cylinder, the rubbers in the calipers...

....the lines themselves.. are they fresh and restriction free??

Are the pistons inside the calipers perfecly straight? Does the pressure applied from the hydraulic fluid forcing the piston out translate to the brake pad hitting the brake disc perfectly square, without taper

Do the pads sit inside the caliper harness square? Did they need to be machined or filed down to make them fit so they may be slightly out of alignment, and causing you to use more pedal pressure than you might otherwise need because they are not perfectly straight?

Are the brake calipers themselves still true and in alignment? If you have had many many hard stops, that may not still be the case, and can put the brake pads at an odd angle to the caliper piston, and require more pedal effort, and therefore generate more heat than if they were all factory fresh....

Plenty of options... putting on brand new CCB's will fix much of this, if you clean the lines out...

 

With your boxer PP,you mentioned that there is almost no ventilation inside the wheels?? If you fitted larger wheels,in turn would cool the brakes a little more. Did you have the standard wheels on it?? Do you remember the "solids" everyone used to put on their holdens/fords years ago(and even today ) Cause the wheel was solid,very little air can circulate around the brakes,and you can get brake fade very very quickly. Trust me,i know that for sure. Now the old girl runs 18's AJR's! hehe. Keeping the caliper cool plays a major part in any cars brakes. Formula 1, V8 Supercars, Fords and Holdens. In the open wheel F1 cars,they even have brake cooling ducting. Even the old Holden VL Turbos had cooling finns on the brake calipers.

 

Dude,all of what you just posted is...........um.........partially incorrect. And why would CC's fix much of it? If you clean the lines out?

 

Partially incorrect?

My point was that the new calipers (whether they were brand new conventional ones, or CCB's) would fix a lot of the issue if the brake lines/master cylinder etc were clean, and with fresh fluid.

I know all about the vagaries of brake calipers choosing to get out of alignment, thanks to some really badly made Girlock units in the mid 1980's... all fixed eventually, but the dealer changed just about everything in the process...

 

I don't understand how the brake fluid could boil, without the pads overheating.

 

The fluid is either of the wrong type/specification, which cannot sustain the method of use, or the lines are restricted/dirty etc.

The fluid can also overheat because of the heat coming from the brake pads/calipers... but a pad can dissipate significant heat without going near the operating temperature.

FF can more likely explain it better

 

they were the standard wheels. there was no air circulation in there apart from whatever passes around at speed.

I don't believe there was any inadequacy outside of the original design. The fluid was new, fresh, unopened from the tin etc etc.

I'm not sure if a CCB caliper, which would obviously make the same amount of heat, would overcome the problem of the boiling fluid UNLESS there is a fundamental issue with the design of the original caliper that allowed the fluid to boil under extreme conditions that maybe a more modern caliper can overcome.

 

More so because brake fluid absorbs moisture very quickly and that reduces the boiling point of the fluid. In extreme cases (more likely track work) the fluid can boil and create vapour in the caliper,which creates vapour lock in the caliper and you lose your brakes

 

which wasn't the case in this instance

 

Castrol SRF fluid is a DOT 5 brake fluid. It has a boiling point of 310c. The good stuff! From what im aware,the brake calipers are the same. I doubt the CC caliper would make any difference in keeping cooler than a conventional brake caliper. Modern caliper or not,they are not much different in design at all.

 

Didnt you mention earlier on that you DID have boiling brake fluid in the boxer??

 

Guys, to leap back into the fray here....

Apologies if I'm repeating a bit from my post earlier in this thread, but I feel like I have to in case it's been lost in all the noise.

THE LIMITING FACTOR FOR STOPPING POWER IS AT THE TIRE, AND NOT AT THE ROTOR.

It doesn't matter if the rotor is the size of a hula hoop or the size of your wedding ring, so long as it can generate sufficient stopping power to lock up the wheel.

Ricers spend lots of money getting bling brakes, with slots, vents, cross-drilling, oversized rotors, painted 8 piston calipers with stainless steel lines, all to stop their Civics while cruising the strip. It's a criminal waste of money. Don't fall victim to this belief. And this applies to ceramic brakes too. Composite brakes are THE thing to have if you're racing F1 or some other series that allows it. But short of that, you do NOT need ceramic brakes for stopping power.

Still don't believe me? Try this thought experiment.

You're in your car, and your buddy is in an identical car, except that you have ceramic brakes (or an "upgraded" brake system with larger rotors) and he has stock brakes. You're both doing 60 mpg (or 160, it doesn't matter) -- on a frozen lake. You both hit your brakes at the same time (assume no ABS). The wheels lock up, and you both slide and slide and slide, until you come to a stop, still side by side. Why? Because the stopping power of the brakes - both types - far exceed the grip provided by the tire on the ice.

Now, repeat the same experiment, only instead of ice, it's pavement, but coated with a slippery detergent/oil mixture. Same result.

Repeat again, but pavement with only regular water. Same result.

Now, same again, but only pavement. Same result? YES - assuming that each braking system has enough power to lock up the wheels (which any car made since, oh, I dunno, 1960 does).

So, is everyone clear? The LIMIT on stopping power is where the TIRE meets the ROAD. Spending money on upgrading brakes in the belief that it will appreciably shorten braking distance is a waste.

BUT, now the theoretical is out of the way, what about the practical?

Sure - I'll admit, I can hypothesize instances where upgraded components might conceivably shorten braking distance. For example, if your new brakes were to allow you to shorten the time needed between pedal application and full caliper clamp, that might translate into a few inches of shorter distance. And if ceramic brakes reduce the total weight of the car by 50 or 100 pounds, that might decrease a few inches too. But this ain't material stuff, gentlemen - any difference will be vastly outweighed by driver reaction time, the pedal pressure in initial application, and other such variables.

So why do people need "upgraded" brakes? Well, for the simple reason that brakes are designed to turn kinetic energy into heat energy. And modern stock brakes do this job thoroughly well. But there are limits, and when they are exceeded, some bad things can happen. Pads can be overheated, and they outgas and leave residue and lose grip. Fluid can boil, causing the water vapor trapped int the fluid to become gas, causing loss of hydraulic pressure. Heck, calipers can melt and fall right off. (oh, and ceramic brakes might contribute to a slightly faster lap time, in part because having less unsprung weight will make a car handle better when cornering.)

BUT NONE OF THIS HAPPENS ON THE ROAD IN A MODERN CAR. Well, sure, if you're a complete ninny who is horribly abusive on the brakes, riding them constantly, while descending a mountain in an overladen minivan, sure, you might boil your old, contaminated, unchanged brake fluid. But even then I doubt it. Certainly no one who's driving any Ferrari built in the last twenty years on the STREET, without running the risk of being arrested and/or shot by the police, will suffer from braking problems. Street use, as compared to track use, simply does not put enought heat into the system, for lap after lap after lap, to require the use of ceramic brakes.

Think about this. Companies like Mercedes Benz and BMW, who spend millions on ridiculous accident avoidance technology like active cruise control and lane control and focus on things like faster-lighting brake lights and computer modulation of brake calipers so they can squeegee off excess moisture and are pre-positioned to engage even faster, and they don't spend the money to put ceramic brakes on their big, heavy sedans, when that technology is freely available in the market today? It's because they know the reality and the physics behind this - you do NOT need ceramic brakes on a street car, as they will NOT decrease your stopping distance on the street.

vty,

--Dennis

 

yes...but not because it had absorbed moisture or any other degradation to its performance.

 

i thought there was some difference in design with some calipers where the brake lines kept fluid more or less on the outside of the caliper, esp around the cross over of the rotor, that allowed more cooling of the fluid...or i could be completely wrong.

 

I know what you are talking about, suppose it may help a little. Nothing too exciting though i think.

 

Are you sure?? Without sufficient air flow around the caliper/brakes as you mentioned because of your wheels,maybe you did manage "boil"your new DOT 5 brake fluid and experienced a vapour lock in the caliper as i mentioned before??

 

yeah..that IS what happened. I thought you meant that it may have absorbed moisture which is what some fluids do over time.