my new rotors

[Shades of Gray]

[markley02]

Why slotted and not drilled? IMO drilled are a lot better for street application

[MuddyREX]

I can't see any of the pics you put up today.....more red x's.

[Shades of Gray]

how about now?

[SilverTurboRidin]

still a x

[htheduck]

Originally Posted by markley02

Why slotted and not drilled? IMO drilled are a lot better for street application

Why is this so? I'd like to know...thanks.

[SexyDSM95]

Originally Posted by htheduck

Why is this so? I'd like to know...thanks.

Supposedly they vent better and prevent from warping where as slotted rotors slowly chip away at the brake pads. But from what I have heard, certain drilled rotors can easily crack.

P.S. When I click the properies of the red "x" and view the page, then refresh the thread the picture shows up. I think it's just how imagestation sometimes is.

[markley02]

Sexydsm95 explained pretty well. Slotted rotors create heat and almost literally "cut" a new slice of pad everytime. You go through pads very quickly compaired to drilled or plain rotors. Slotted rotors are made to take the glazing off of pads. That is why some cars come stock with drilled rotors and not slotted. To my knowledge there is no car that comes stock with slotted rotors. As for drilled rotors cracking, I have heard of cheap rotors cracking. You get what you pay for.

[TROLL]

interesting because i have always heard that slotted rotors are better for street applications and drilled rotors are just for show. reason being that slotted rotors still maintain almost all of their strength but drilled rotors, although effective, crack under too much heat/wear.
bryan

[markley02]

I am not 100% positive about the things I have said in my previous post, but I am sure about some porche, bmw, and MB's come stock with drilled rotors. I dont think they would put drilled rotors on a 911 TT just for show.

[igo4bmx]

slotted vs drilled (or both)

slotted as stated, helps with shaving brake pads to give a nice pad surface to break with.

drilled rotors are meant to help cool.
IMO a drill rotor is not better than a non-drilled rotor...

non drilled rotors offer a larger surface area, and more surface area equals more braking power.
you see drilled rotors on brake setups when the rotor are large enough to allow drilling to be accepted...

if you had stock 11inch rotors, and went 11 inch drilled- braking would be worse
if you went to 13 inch rotors, and got the drilled rotors, braking would not be sacrificed and then you would have better cooling.


and drilled rotors only crack if they were poorly drilled....
i've seen too many people buy drilled brembo rotors on ebay (honduh guys) only to realize the seller bought non drilled rotors (cheaper) and drilled them themselves to make more money!

so whenever you buy drilled rotors, make sure they came like that from the manufacturer!

[htheduck]

Inferior drilled rotors crack under stress....Mass as well as surface area is removed from the original rotor and the weakest parts are generally located at/or near the machining processes. (However, I do not know the process for Porsche brakes-which are some of the best in the business.)

For heat dissipation, you generally want more mass to dissipate more heat. (There's the obvious negative about more mass).

There are many avenues to go into the right set of brakes-all depends your budget and what you want them to do for you. You need to find/research your own answers for form vs. function. (Ever consider marketing - as the reason some of these high end cars have drilled rotors stock? - Just don't believe everything you see.)

[markley02]

Originally Posted by htheduck

For heat dissipation, you generally want more mass to dissipate more heat. (There's the obvious negative about more mass).

There are many avenues to go into the right set of brakes-all depends your budget and what you want them to do for you. You need to find/research your own answers for form vs. function. (Ever consider marketing - as the reason some of these high end cars have drilled rotors stock? - Just don't believe everything you see.)

Sorry, but I highly disagree with you. More mass doesn't dissipate more heat. It is all about surface area, not mass. (I dont quite understand what you are saying, maybe I am reading it wrong)

There is a reason high end cars have drilled rotors and it is not for marketing. The gt2 and gt3 are purpose built cars.

P.S. sorry to keep derailing this thread. Look wise, i think that they are awesome.

[snakeeyes]

Originally Posted by markley02

Sorry, but I highly disagree with you. More mass doesn't dissipate more heat. It is all about surface area, not mass.

There is a reason high end cars have drilled rotors and it is not for marketing. The gt2 and gt3 are purpose built cars.

GT2 and GT3 have drilled rotors for roadrace applications where cooling under extreme heat is the primary goal. You will never ever experience road racing conditions on the street and therefore drilled rotors are practically worthless for street applications, and in fact reduces braking performance due to the factors mentioned before (less mass, less structural integrity).

Furthermore, even under road race conditions, you are better off trying to design ducting towards your brakes for maximum cooling rather than drilled rotors for alleged heat dissipation, because the drilled rotors are likely to crack under the stress of prolonged heat.

In summary, drilled rotors are for the most part for show, no go.

[SmokeyBandit]

Suprised no one has mentioned the most basic thing. When pads really heat up and outgas, slots and holes provide a place for the gas to go so you have pad to rotor contact.

Carroll Smith has said in his books such as "Engineer to Win": Drilled holes do everything slots do, only better. This is really only vaid for the soft race pads where the the pad material (as it is scraped) gets clogged in the slots, rendering the slots useless.

[markley02]

Originally Posted by snakeeyes

GT2 and GT3 have drilled rotors for roadrace applications where cooling under extreme heat is the primary goal. You will never ever experience road racing conditions on the street and therefore drilled rotors are practically worthless for street applications, and in fact reduces braking performance due to the factors mentioned before (less mass, less structural integrity).

In summary, drilled rotors are for the most part for show, no go.

I have felt my rotors heat up on the street. The last thing I want are soggy brakes while I am going down a hill at 60 MPH. I was praying for cooler brakes at that point. So what is better, more braking surface or the loss of rotating mass? Under normal driving conditions I do think that drilled rotors are worthless, but for my driving style I do not think they are worthless. I must agree though, they are "no go" they are "for stop" 60-0 is important. As them being "for show" I think only 10% of the people who own them use them for that purpose.

[htheduck]

Originally Posted by markley02

I have felt my rotors heat up on the street. The last thing I want are soggy brakes while I am going down a hill at 60 MPH. I was praying for cooler brakes at that point.

Not knowing exactly what you drive-the weight bias of your car is not clear for this discussion. The conditions in which you described about heated up rotors on the street and the prayer for cooler brakes is a little vague. Sorry but it's going to take more than a prayer to solve this problem. Snakeeyes has the right idea about a suggestion for a better brake system. Your current symptoms could possibly be basic maintenance: compromised lines, glazed pads, air in the lines, contaminated fluid, etc.

[Shades of Gray]

so what does everyone think of my rotors?


lol
;o)

[htheduck]

Nice...I like your calipers better.

[99SL2_Modder]

Originally Posted by SmokeyBandit

Suprised no one has mentioned the most basic thing. When pads really heat up and outgas, slots and holes provide a place for the gas to go so you have pad to rotor contact.

Carroll Smith has said in his books such as "Engineer to Win": Drilled holes do everything slots do, only better. This is really only vaid for the soft race pads where the the pad material (as it is scraped) gets clogged in the slots, rendering the slots useless.

Actually, I'm going to bring up a dead thread.

Conventional pads nowadays do not create a gas, thus the drilling doesn't help gas venting at all. Unless, of course, you're using pads from the 50's.