Club Scion tC

Car Candy Motor Sports
Guest Menu
Scion News
Scion Generation
Scion tC Parts
Aftermarket Scion tC speed shop carries Scion tC exhaust, Scion tC intakes and more Scion tC parts at ScionGeneration.com
Club Scion tC Decals

Show your support for the club and sport some Club Scion tC premium decals on your Scion tC.

Get them now for only $5 shipped! Available in either vinyl or static cling.

Forum Options
Register | Login
Advanced
Viewing Thread
Home > Performance Mods > Suspension & Brakes > Big Brake Kits

Big Brake Kits

Pages: << 1 2
Related threads: ( Click here to view )
dsm3383
Rochester
New York, US
  • Scion Guru
FrAnkRYzzO wrote:
^^That's what I was thinking. I was doing some research on rotors today and I kept finding the same conclusions:

1. That any rotor with a hole through it increases the chances of cracking (cast or drilled)

2. Casting the holes reduces this risk but does not eliminate it

3. That the only benefit drilled rotors provide are for water removal or for lightening the rotor (useful on a motorcycle)

I actually found the same quote from SCR Check out this link I found. It's a discussion about this same topic on an rx-7 forum. There are a series of quotes from brake designers and manufacturers towards the bottom of the thread that seem relevant to our discussion:

http://www.rx7club.com/showthread.php?t=480082&page=2





Yes, adding holes or slots will increase your chance for the rotor to fail but thats because you have less material and stress concentration points.

What I stated was talking about the material only. Those points cold worked in the rotors from machining will be stronger. This is just infering to the material not the design where reducing material and adding stress concentration points will increase cracking and failure.

And second I will disagree again about "cast in holes stronger than machined". First of all the rotors are machined after cast which includes the holes. So all the cold work from machining already exists in the rotor completely including the cast holes since they are cleaned out through the secondary machining processes after casting. Second, failure mechanics states a materials surface finish plays a huge role. A machined surface has better fatigue strength than non-machined (cast) in consideration to failure and lifetime use of the part.

You will have breaks in your grain boundaries from the secondary machining process and it plays no role in strength. Steel is judged on its strength by the "dislocations" in the microstructure of the material. Dislocations are pretty much the carbon atoms that are free and not bounded by other molecules in the steel. Grain boundaries really do not have any effect.

Like stated earlier. The material and any processes added to the rotor is pretty much the defining characteristic of its performance.

I am trying to educate the public through my extensive knowledge in engineering so not trying to bash or seem prude.

I have to admit I know alot and since I made engineering my profession and life it is easy for me to understand. I want people to understand this cause I do know at times I explain things horribly ahaha. I sometimes fall on my face to make my points and have the general public understand.

Beer is proof that God loves us and wants us to be happy.

-Ben Franklin
[#] Feb 19, 2008 06:59pm
TC1032
Philadelphia
Pennsylvania, US
  • Tire Changer
 thanks guys but this brings up another question.
if the tires do most of the work.
what's the point of getting rotors or better brakes ex. EBC green stuff.

[#] Feb 19, 2008 10:52pm
Mayo
Rockville
Maryland, US
  • The Guru
 Why get quality breaks? Im gonna take a shot at this, but Im sure they'll last longer. That, and it would increase the coefficient of friction ( 'u' in Ff = u x N) helping you stop better.

But I suppose it would make sense to get tires first.


"gonna wash my car before i take a nap.. can't rest well knowing i've got the entire cast of A Bug's Life on my bumper" - Vicious
-- Want to post a "For Sale" thread? Check out the rules first.
[#] Feb 19, 2008 11:01pm
WendysOrBust
Dallas
Texas, US
  • Window Washer
TC1032 wrote:
thanks guys but this brings up another question.
if the tires do most of the work.
what's the point of getting rotors or better brakes ex. EBC green stuff.


Yes, Mayo got most it right. The reason for upgrading to different pads are vast. Just like tires there are allot of trade offs to be had with different sets of pads; dust, noise, durability, heat range. Most streetable pads, or pads that come from the factory are designed to be very quiet, and to have long durability. They are not designed to be consistant when reaching "race" heat and usually the materials used do not apply enough friction to the pad. When upgrading to lets say, the EBC-Greens, you sacrifice some comforts such as, noise, and dust build up, but the trade off is that you now have a pad with much better "bite" and one that will take a certain amount of abuse in high temperatures. Make sure the pads you purchse suit your needs and your driving habits. You don't want to "over purchase" to a full on race pad that is only designed to be operated at race temperatures.

[#] Feb 19, 2008 11:37pm
FrAnkRYzzO
Perry Hall
Maryland, US
  • $upervillain
    for Hire
 I really enjoy these in depth discussions, especially when we have contributors who can offer more then just an unfounded opinion. I've learned a lot so far about braking systems in this thread, and I think there's just a couple points left that could be clarified.

Here's what I've gotten out of this so far:

Upgrading to a big brake kit on a street car is basically just for bling factor. The problems that a BBK solves (heat fade) are not experienced in regular driving situations.

The most determinate factors in stopping power are your tires and your pads. The higher the coefficient of friction in the tires, the more gripping power they have against the road, and the less likely they will lock up the brakes and cause the abs system to activate.

The preferred rotors in racing applications are slotted or flat rotors, and drilled rotors are mainly for looks. The advantage to drilled is that they tend to channel water better in wet braking situations but they also have a higher chance of cracking from the repeated stress of braking.

A drilled or slotted rotor does help to keep the surface of the pad fresh and channel away the brake dust, but also shortens the life of your pads.

Also, the opinion that I have formulated based on the research and discussion is that oem style rotors with strong pads would seem to be the way to go. It seems as though you need to match the pads to the rotors though because both are wear items that will eventually need to be replaced. A harsher brake pad like a ceramic will kill your rotors, so why use something like that on expensive ones? Both are relatively the same price to replace, so I figure choose one or the other as your regular maintenance item. Right now I'm running Axxis Ultimate pads on OEM rotors, and the stopping power over the stock pads is night and day.


What I still don't know:

I was discussing this with a friend of mine who stated that the primary advantage to having drilled rotors is that they don't warp, where slotted and flat will. Anyone find any truth or problem in this statement?

DSM: I am by no means trying to contradict your engineering experience, but I still don't understand how machining the holes can provide a stronger final product then casting them. I'm not saying that you're wrong, just that your experience contradicts all of the research that I have come up with, and I have been unable to corroborate your assertion. Is there any way that you could point me to some research material that I can read up on?

Oh yeah, stickied

...............

Search or one of these adorable kittens WILL DIE!
[#] Feb 20, 2008 11:54am
dsm3383
Rochester
New York, US
  • Scion Guru
FrAnkRYzzO wrote:
DSM: I am by no means trying to contradict your engineering experience, but I still don't understand how machining the holes can provide a stronger final product then casting them. I'm not saying that you're wrong, just that your experience contradicts all of the research that I have come up with, and I have been unable to corroborate your assertion. Is there any way that you could point me to some research material that I can read up on?

Oh yeah, stickied


http://en.wikipedia.org/wiki/Work_hardening

Anytime you machine metal you work harden the material. The above reference states it quite well. I would recommend just reading and understanding the definition. The rest is all materials science and will be out of your realm unless you took a materials science course in metals.

Also, nice wrap up of the information in the post Frank!!

Beer is proof that God loves us and wants us to be happy.

-Ben Franklin
[#] Feb 20, 2008 12:26pm
FrAnkRYzzO
Perry Hall
Maryland, US
  • $upervillain
    for Hire
 Thanx :mrgreen:

I'm going to try and get through that, and if I have any other questions I'll let you know.

...............

Search or one of these adorable kittens WILL DIE!
[#] Feb 20, 2008 12:50pm
dsm3383
Rochester
New York, US
  • Scion Guru
 Here is an interesting thought.

Work Hardening is a phenomenom that occurs to steels through various processes. Machining is a very common one of these processes.

Let's look at a rotor. During the lifetime of a rotor it sees material removal from the pad wearing at it through use. You can compare this to a machining process and can assume that you work harden the material of the rotor through its lifetime.

It would be interesting to conduct a metallography study of a brake rotor before and after a lifetime a use. How much harder does the material of the rotor get compared to its original state? That would be cool to know.

Just a word of thought for today.

Beer is proof that God loves us and wants us to be happy.

-Ben Franklin
[#] Feb 20, 2008 02:59pm
WendysOrBust
Dallas
Texas, US
  • Window Washer
FrAnkRYzzO wrote:
I was discussing this with a friend of mine who stated that the primary advantage to having drilled rotors is that they don't warp, where slotted and flat will. Anyone find any truth or problem in this statement?


I've never heard of this before, I know plenty of people that track their cars just fine on slotted or blank rotors. The only real benifit from drilling your rotors comes from reducing unsprung and rotating mass. But this is really only applied to motorcycles, and older style F1 cars.

http://flashoffroad.com/Maintenance/Brakes/BrakeRotors.html

Good link in which several brake experts discuss drilling, slotted, and blanks.

[#] Feb 20, 2008 03:01pm
FrAnkRYzzO
Perry Hall
Maryland, US
  • $upervillain
    for Hire
 I couldn't figure out if there was any merit in his assertion about the warping either, but he seemed very certain about it. (not that that means anything) His logic was that the warping of rotors occurs more frequently then the cracking of rotors, and from a probability standpoint you would have less chance of a damaged rotor by switching to drilled. Now there are definitely two flaws in his argument:

1: It assumes that drilled rotors can't warp. Which he was unable to prove to me aside from hypotheticals.

2: Because the majority of rotors in use are oem, then from a statistical standpoint, of course you will see a higher percentage of warping vs cracking. Without having the actual data to compare with a ratio analysis, there's no way to determine if cracking is more prevalent then warping without a controlled environment.



...............

Search or one of these adorable kittens WILL DIE!
[#] Feb 20, 2008 03:45pm
Web
Maryland, US
  • THE SHADOW
 Warping is actually MORE common on drilled rotors than slotted or flat rotors due to the higher cooling and heating cycles it has. The metal flexes and fluctuates in temperature to much and so quickly that it disrupts the structure of the metal.


Complaining is futile when you supported the victory.
http://clubsciontc.com/fo...-rims--5x100-pattern.html
[#] Feb 20, 2008 03:58pm
Orin
Auburn
Alabama, US
way to steal my fire guys, I was looking forward to some cheap eBay drilled/slotted rotors



I think I'll just upgrade my pads

[#] Feb 20, 2008 05:15pm
TC1032
Philadelphia
Pennsylvania, US
  • Tire Changer
 wow i never expected my first question to lead to such a informative discussion. None the less, I'm guessing I should get pads instead of getting a 'Big Brake Kit' per say.

so to clarify..
slotted over drilled..
tires and pads over rotors..
right?

[#] Feb 21, 2008 01:52am
Web
Maryland, US
  • THE SHADOW
 Yes


Complaining is futile when you supported the victory.
http://clubsciontc.com/fo...-rims--5x100-pattern.html
[#] Feb 21, 2008 07:41am
nick06tc
Virginia, US
  • Scion Guru
 I say yes as well.

But dont go to high tech/high performance or you will bypass the effects. High performace/race pads work best once they have some heat. and will give off ALOT ALOT ALOT of break dust!!!!!

But tires are deffinetly number one, no matter how well those brakes, brake, if the tires dont grip, you will never stop!!!!!

[#] Feb 21, 2008 04:00pm
falkore24
New Jersey, US
  • Vehicle Designer
 Hello all .... I realize that I'm new to this forum and I don't mean to stir up a lot of commotion on my first post, but I wanted to clear a few things up.

First, when metal breaks due to fatigue, creep or any other catastrophic failure, it is along the grain boundry, so to say that the grain boundries have nothing to do with the rotor's strength is just wrong.

Second, the post relating the cast holes as in Brembo's design is on the money. Machining holes afterward do present exposed, discontinuous grain boundries to lead to cracking.

Third, rotors are heat treated throughout their lifetime. Their usage is more of a heat treatment than a machining process, although they can be viewed as one and the same. I see it more as a heat treatment since the friction hrdly reduces the rotor material, but it sure heats them up quickly .... the hardening comes in when they rapidly cool, especially when it's wet outside.

Fourth, about the BBK discusion ... not refering to the wheel weight, but with wider, stickier tires, the big brakes may have some possitive effect. The rationalle has already been discussed via the tires sticking to the road enough to allow more force to be applied. Also, the same total amount of force applied further from the center of the wheel will afford more stopping power by converting that same clamping force to a larger torque arm .... more stopping torque. I still don't think that BBK's are worthwhile for normal or even spirited street use unless you live in an area where your daily drive can be compared to a canyon run.

Lastly, I want to commend dsm and others for bringing a very high level discussion to the board. Dsm, I see that you graduated from RIT. That was my second choice, but I found that the atmosphere at Virginia Tech was more suitable for me.

That's it for now, but you can all expect to see me around where I can find these types of discussions and some others that I am interested in.


EDIT: One last thing .... rotors are sprung mass.

[#] Mar 30, 2008 11:29pm
LB11
Boca Raton
Florida, US
  • Oil Changer
 I would like to add something as well.

Im not arguing with the information in the thread because I agree with most of it. But to completely say bigger brakes are a waste of time is not correct. The biggest benefit is pedal feedback and the ability to modulate it at the limits. The TC does have a fairly decent brake system and I dont have experience with a larger system on our cars. However, I did place larger brakes on my old car and while I could lock up the tires easily with the stock brakes, the larger brakes made the pedal feel much better and it was much easier to get the maximum braking force applied without locking up the brakes.

With that said, I would definitely recommend pads and tires first. Then if that doesnt suit you, you could look into something bigger.

Personally I would just use a solid rotor. No need for slotted or drilled. Unfortunately its impossible to tell if they help without having a tests performed in a controlled environment which most likely none of us can provide. Someone might argue that holes or slots will reduce contact surface area which is more beneficial than the minimal gains of other benefits in a daily driven vehicle.

[#] Mar 31, 2008 11:24pm
dankh
Houston
Texas, US
  • Window Washer
WendysOrBust wrote:
The point I was trying to make is that on a street application it is almost pointless to upgrade to such a big kit, without doing the basics first.


So what are the basics in terms of upgrading my brake system?

EDIT: Pads and tires.

UPDATE: Turns out I can read.
[#] Oct 09, 2008 02:13am
java09
Honolulu
Hawaii, US
  • Godlike Advisor
 lookie lookie what i got in teh mail:

















install friday night!!! yipeeeeee!

2008 Turbo Scion tCizzle
POWERED BY TURBOTOYOTAS!
310WHP, 272WTQ
more to come_..
[#] Oct 09, 2008 02:49am
LiLee
Lowell
Massachusetts, US
  • Scion Guru
 did the dr pepper come with it too?

Random of the day: Happy Birthday TheFantasticG!!
[#] Oct 09, 2008 02:50am
java09
Honolulu
Hawaii, US
  • Godlike Advisor
 thats a diet dr pepper and YES it did!

nah jk, it didnt but they should!

2008 Turbo Scion tCizzle
POWERED BY TURBOTOYOTAS!
310WHP, 272WTQ
more to come_..
[#] Oct 09, 2008 02:57am
LiLee
Lowell
Massachusetts, US
  • Scion Guru
 lol.. ^_^ is orange the new in color?

Random of the day: Happy Birthday TheFantasticG!!
[#] Oct 09, 2008 03:07am
java09
Honolulu
Hawaii, US
  • Godlike Advisor
 they are actually a very nice coca cola red but the flash makes them look a tad bit orange!

2008 Turbo Scion tCizzle
POWERED BY TURBOTOYOTAS!
310WHP, 272WTQ
more to come_..
[#] Oct 09, 2008 03:08am
LiLee
Lowell
Massachusetts, US
  • Scion Guru
 well.. they look sweet, can't wait to see them on the ride.

Random of the day: Happy Birthday TheFantasticG!!
[#] Oct 09, 2008 03:17am
java09
Honolulu
Hawaii, US
  • Godlike Advisor
 thanks!

2008 Turbo Scion tCizzle
POWERED BY TURBOTOYOTAS!
310WHP, 272WTQ
more to come_..
[#] Oct 09, 2008 03:50am
Pages: << 1 2

TOP: Home > Performance Mods > Suspension & Brakes > Big Brake Kits



Quick Nav:
©2008 Club Scion tC - Community for Scion tC enthusiasts.