ares

iTrader: (2)

both models can engage ABS, I know your a smart guy, so I know you know what that means. both brakes possess the power to bring the car to a nice sliding stop in a cloud of smoke. agreed? both cars also have identical tread, same size, same profile, same everything. so how can you possibly say that brembos stop faster in a single stop? if the brakes are both able to stop the tire so much that they lose traction, and they have the same amount of traction, both stop equally.

you would of course think, WOW these brembos stop on a dime, but what you might not realize, is so do the stock brakes.

As for your day racing, 30min laps? ummm yeah, thats gonna invoke some MAJOR fade from the stock brakes, so much that they will no longer be able to invoke ABS. no arguement, but of course this wont happen after 10 or 20 stops, but in 30 minutes, you will stop hundreds of times. in street racing tho, you wont stop more than 10 times, or I would imagine anyway, cause Id sure hope your not tearing around the streets for all that long in a run...

DmitryZ

woohooo.

so if I wreck my Z, my 240 gets nice brembo rotors!!!!!



j/k


sorry I was bored

tbcz

Exactly.

No one disputes the fact that on a track the Brembos are the way to go. But with a cool set of brakes, Brembo or stock, there is going to be negligible difference in their stopping distance. Mash either one, and the only determing factor is going to be tires and ABS...only after the onset of fade will there be a difference.

bhobson333

On the surface, your logic is irrefutable. If the brakes can engage ABS in any way at all then the weak link must be the tires. Think deeper into it, though, to the physics of one hard braking action.

The basic function of braking is to turn kinetic energy (motion) into heat, and then to dissipate the heat.

With bigger rotors and calipers, more friction surface area, better heat dissipation, more pad-to-disc stability (from more pistons pushing on the pads) you get a cooler disc surface and a cooler pad material after the same amount of braking, right?

When the pad material gets real hot it gets sticky; turns into tar. You've all seen that tar-like substance on your wheels after hard braking, right?

In one hard brake, the surface of the pads gets hot, gets sticky, eventually causing the brakes to lock and the wheel to slide or instead for the ABS to kick in. Cooler pads would cause the ABS to kick in later.

Have you ever had ABS kick in? You don't get better braking with ABS than before ABS, you just get better braking than if it had instead been wheel slide. You're better off if you can avoid ABS altogether. Stickier tires is one way to achieve this. I maintain that cooler discs and pads, even on one isolated braking maneuver, is another.

I'm not an expert. I only report my experience. I fully admit to the possibility that you are right, that I am overly impressed with my brakes. I find it unlikely, though. I guess we need to go to a skidpad to find out for sure.

johnnyzcar

Hi all,
I haven't posted that much but I felt compelled to mention that I have also considered the difference between the standard vs. the Brembo. I drive a Z32 with drilled Brembo rotors and Hawk high performance pads. The Hawk pads are used by quite a few SCCA racers (stock classes and full blown race class)The pads are designed to be effective at certain temperature ranges and the coefficient of drag increases as heat builds. I must point out that the drilled rotors do allow the gases to escape because the pad will flash at extreme temps. The preferred is a slotted rotor because of strength but they are more money. In my personal experience the 4 piston drilled rotor combination has a much better pedal/brake feel to me the driver. They are much more responsive to pedal input and my stock pads were not acceptable to me during street use. I am not a street racer but I drive agressively. Most of my driving is stop and go but if your heavy on the brakes and the Z is a heavy car and if you wait to brake late, the stock brakes will fade and the Brembos wont. When I have driven a few friends vehicles I constantly don't brake early enough for stop signs because I am so used to my brakes. Just for the brakes alone you are better off with the Track version. That will be my choice when I place my order.

Just my 2 cents, good luck with your Z.

D'oh

Actually, ABS always stops faster than non-ABS. The reason is its consistency and that is allows the driver to rapidly press the brake and reach impending lock up. If you try to threshold brake, you will only end up spending most of your time away from the threshold, not to mention the fact that you need to ease into the brakes much more softly than you can with ABS. One example that shows this very clearly is the R&T 0-100-0 test from this month's issue. If you look at the Saleen S7, it was the fastest car 0-100, but significantly slower than the others going from 100-0. This is because it is not possible for a driver to brake as well as ABS. Therefore, if both brakes can engage ABS, they will stop the car in very similar distances.

However, after tracking my car, I've found that even more important that actual performance is percieved performance and the confidence (or lack thereof) that accompanies it. I found that my standard brakes would last for about 3/4 of a 20 minute session and then start to experience slight fade. Because the fade was disconcerting, I began to adjust my stopping distances to try and save the brakes a bit. On every lap the instructor told me to brake much later, but I could never get myself to do it simply because I was not confident enough in the brakes. This affected my lap times only slightly, but it was noticeable.

Now, I had planned on getting stoptech brakes instead of the brembo's (since they are only $2000 as opposed to the $5000 premium of the track Z over mine), but since the brake upgrade will bump me out of the stock SCCA AutoX class, I am no longer sure if it's worth it since I rarely track the car.

Anyhow, if you plan on modding and tracking your car, then I'd get anything other than the track model and use the saved money for mods.

If you plan on AutoX and no track, than any version would be fine.

If you plan on AutoX and track, and need to stay stock, then you should get the track version.

IMO...

-D'oh!

daytona350z

iTrader: (19)

couldnt have said it better myself..
i am in the process of upgrading my touring brakes to track model ones. i got the for a steal so there was no hesitation. got em for about 1.2k with rotor, lines, pads, and calipers...less than 2k on them.

i am planning on auto-x and some track, so these are just perfect for me.

i do enjoy reading these posts very informative.

Buub

iTrader: (1)

Bhobson333, what you are saying does not contradict what these other guys are saying. Every example you have used has involved braking over time with hot brakes. This is the advantage of expensive high-power brakes.

But you cannot change the fact that the brakes cannot brake your car any harder than the tires can hold onto the road. The tires are the defining factor. Stock brakes, Brembos, Stoptechs, etc. will all stop the car in the exact same distance/time if the brakes are fresh and cold. They will stop the car in exactly the shortest distance/time that the tire traction on the road will allow.

But yes when they start to get hot the stock brakes will fade a lot sooner. One perceived difference that makes it feel like the Brembos brake harder is that they can cause the ABS to kick in with less pedal effort. But slam the pedal down with cold stock brakes and you'll actually get the same stopping distance.

bhobson333

You must have mis-read me. In my last post I said:
I believe we have gotten to the point where I won't convince you and you won't convince me so we'll have to agree to disagree.

bhobson333

At the request of a reader I just checked my pads.

At 10,000 miles I have a good, solid quarter-inch of pad left, front and back.



That's after 8 months of aggressive driving including a weekend at VIR South (a course with a reputation for eating brakes alive) that killed the brakes of three Tourings.

tbcz

Well this gets more into the issue of what stops a car quicker, human or ABS? This is a much more complicated question, with many more variables. Your theory presupposes that the ABS stop will be less efficient than the non-ABS stop. That's a tough one to answer...

ares

iTrader: (2)

itd be nice if that test had shown every stop distance, but they give best and average, but the results are hard to infer. the best for the brembos are much better than the best for the stock. but then you look at average, and the best for stock was like 2feet under the average, and the best for the brembo was like 4 under the average.

does that mean the brembos start out very strong and fade? I dont think so...

but I also dont think you can say they both got there best stop the first time, the brembos must have gotten one good stop for whatever reason, cause I would expect the brembos to have a very even distance. but there best is so far under their average.

bhobson333

IMHO we're getting close to the truth of the Stoptech report here, namely that Stoptech presented the data in a manner that made them look the best. It's what any company would do.

johnsZ

hi to all...
re- pads touching- yes pads may touch at any time - the disc is rotating, and the pads float in the calipers just a little- otherwise if they were rigid, the braking effectiveness would drop or the rotor would gradually be ground down to the angles of the pads. there is no noticable drag from this. If the pads are a long distance from the rotor, then you get long pedal travel- this is an indication of pad wear. The rotor wears a little, but the pads are the real wear part.

the pad properties- like metal-filled or metal-composites vs. asbestos-based pads vs. other compounds all work basically the same, but vary in their ability to take heat from repeated braking, how they dissipate the heat, and how the friction properties change with heat. The pads on a Mercedes for example, are made very soft so that they never squeak- this is important I guess- but they make a phenomenal mess of the front of these cars. They also, therefore, require replacing at short intervals- my brother got so fed up changing brake pads and the cost of maintenance, that he bought a G35 and an Escalade to replace the 'benz....

the huge brakes are cool looking- an important thing! but for all but racers, unnecessary- see several posts on this point.
there is a huge debate on the value of slotting and drilling, and cast slots and machined slots, etc. For us on the road- it is the appearance over the effectiveness or need. For the guys that actually race- there is the value- keeping the brake temperature down is important- hence vents, vanes, slots, holes, etc.--However, it is also important to note that the swept area is DECREASED by these mods- so you need a larger brake rotor and pads to maintain the same braking power- or more piston area (like 4 or 6 pot calipers), but then you need a larger master cylinder to move more fluid, and possibly a larger booster to get the pressure high enough- so it is a package deal... One guy whom is really helpful is Mr. Baer of Baer Brakes in Phoenix- very knowledgable. The guys at Willwood are similarly helpful.

Also, some of the posts are looking at stopping distances- this is not just the brakes- if the brakes lock the wheels, then the stop is skid limited. The braking distance is affected by weight, tire area, tire compound, road surface texture, dirt, brake area, brake pressure, pad material, caliper piston area, rotor swept area, boost, etc. If you want to stop a little (only a little) shorter, drop the tire pressure to increase the tire contact area on the street. But, handling may get a little squirrely. Look for a softer tire compound (less than 300- like the 260 rating on the standard tires) but be willing to put up with feathering and rapid wearout...

If you want to see real disc brakes at work, watch the PBS show where they test the stopping power of a 777 airplane with a full load.... quite impressive as they turn bright red, then yellow-white and then burst into flames....but still stop the plane from ~240MPH.

old_s13

iTrader: (1)

If you are a good driver and know how to module your pedal, you should be able to do a better job than an ABS equipped car. I dont like nor do I beleive in ABS, its just a failsafe feature that is designed to make people feel safe and take the thinking and risk out of driving. Everyone has their preferences, for me.. I just DONT like ABS.

As for the Brembo brakes, its all about design. Look at the calipers, do a brake job and take them apart.. the difference in build quality and craftsmanship is OBVIOUS. Its a much better system, you can not only SEE the difference, but also FEEL it when driving. Fixed calipers are just a better design, period.

Again, I think we all agree that the main difference is not in braking distances.. its in REPETITION. Hands down, the bigger brake setup WILL do a better job.. over and over, and over and over.

POWERZ

I can't believe this thread stayed on topic with a quote like that!

Blue Liquid

lol

D'oh

I partially agree with your statement regarding brake size: that bigger is better. This is definitely true to a point, but eventually you will reach a size at which the termperatures begin to go down very slightly, and as you add bigger brakes, all you will do is add weight. This size depends on your car, driving habits, the specific track, etc. I would agree that the stock Brembo's are great for the Z, and going to a bigger size would not add significant benefit.

However, I disagree with the ABS stopping distance argument. There are two main reasons why ABS will stop shorter than non-ABS (I won't say that ABS is "better" since there are subjective aspects to that). One reason is engagement time. With ABS you can slam on the pedal and reach impending lockup almost immediately. Since you are travelling the fastest when you first start braking, this can save significant distance. Second, the consistency of ABS can not be reproduced by a driver. While an expert driver may be able to threshold brake most of the time, they will occasionally make mistakes and brake too hard. F1 drivers are always locking a wheel and flatspotting tires, so even the best drivers make mistakes, especially when they try to outbrake a competitor to make a pass. Once you lock a tire, you are lost. First, you need to release the brake until that tire starts to slide again, second, you need to carefully get back on the brakes without locking them again. Also, test data of some of the worlds highest performing cars backs up this argument. In the R&T test I mentioned above, every car with ABS stopped significantly shorter than the only one without it (the S7). From what I recall, the final results were also based on the best stopping distance, not the average, so the ABS consistency advantage wasn't even taken into account. I guess someone could try to stop the Z without engaging the ABS, to see if they could actually make it stop more quickly, but given the results of other vehicles, I think that test would again show that engaging ABS can stop the car soonest.

Now, I can understand why people wouldn't like ABS, since the pedal feel is disconcerting, and it's just one more instance of control being taken away from the driver. However, to downplay its capability as "just a failsafe feature that is designed to make people feel safe and take the thinking and risk out of driving" is just silly. Not only does it make people "feel" safe, but it actually makes people safer. And how is reducing some of the risks in driving a bad thing?.

Finally, like you said, ABS only activates if you F-up and lock the wheels. Therefore, a strong argument can be made that if a driver is actually as good as he thinks he is, he wouldn't be able to tell if he had ABS on the car or not, since it would never be engaged. And then, if by some fluke chance it was engaged, that driver could pump the pedals manually, as if the car never had ABS in the first place.

Airbags I can do without, but ABS is critical in a street car.

-D'oh!

Blue Liquid

D'oh! You present a very logical and well thought out case. I will be forced to agree with you 100%.

bhobson333

This has been a good discussion of ABS but.... I think you guys missed my point.

Let me try to explain it: Take a Track and a Touring in a cold-brake hard stop: same speed, same weight, same tires, same brake temperature, same brake pedal pressure.

As they stop the car, because they have less heat-dissipation capacity than those of the Track, the Touring's brake pads and rotors are going to get hotter than the Track's. As they get hotter the pad's coefficient of drag gets higher (the pads get stickier). Thus, all things being equal, the Tourings wheels will tend to lock up sooner, engaging ABS sooner.

Assuming the wheels never lockup (wheel lockup is theoretically impossible with ABS), a braking system stops the car faster with ABS not engaged (constant pressure between the pads & disks) than it does with ABS engaged (rapid pulses of pressure). Thus if you can avoid engaging ABS with the same amount of pad-disk pressure you will stop faster. The Brembos do this by dissipating the heat better.