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i as well have tracked and auto crossed my car. The time that the car is on an autox course is what 60 to 120 seconds at a time, hitting minimal speeds compared to the track, and minimal braking needed.

in my experience, i have done two full track days (running 4 1/2 hour sessions each day and two autox sessions), and im still on the same rotors and pads for 3 years now.... as with some of my friends who are on blanks and lost 50% of their pads alone on one track day. coincidence ?
 

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I can understand the use of drilling on a carbon ceramic rotor where the material is compressed similar to a forging process which makes the rotor considerably stronger. Also a carbon rotor needs more heat to get to its proper operating temperature, and as it has been stated drilled rotors cause more heat to be generated it only makes sense to drill the rotors. When it comes to rotors its all in the metallurgy.
 

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2000 2.5RS BRP Rsti
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i as well have tracked and auto crossed my car. The time that the car is on an autox course is what 60 to 120 seconds at a time, hitting minimal speeds compared to the track, and minimal braking needed.

in my experience, i have done two full track days (running 4 1/2 hour sessions each day and two autox sessions), and im still on the same rotors and pads for 3 years now.... as with some of my friends who are on blanks and lost 50% of their pads alone on one track day. coincidence ?


^^ assuming your running cross drilled as well?
 

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13 Years of RS
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For a daily driver, slotted/drilled rotors don't help. Fade isn't a problem for emergency stops, that's something that happens at the track with repeated and long use of hard braking. And when cold, slotted/drilled technically have less braking power because there is less surface area for the pads to grab. But I know that what I say won't matter to anyone, this topic is like politics and religion; we all have our opinions, and what I say won't change your mind and might just piss you off.
 

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ok I am going to throw a little motocross reasoning at you guys here. I am not sure how many of you follow motocross but I raced amateur nationals for many years and although I dont race anymore (broken back) I still wrench for many of my friends. Bikes see more brake abuse that almost anything. Back in the early two thousands slotted rotors were the way to go to keep thing light. That is what came stock on them and everyone used them except for mud races. We found that mud and grime would get in the slots and have a very adverse effect on bad life and and braking (small amounts of mud making its way between pads and rotors in between brake applications). We started running solid rotors to combat the grime problem but experienced worse brake faded (not cooling well enough). The solution? Wave rotors. Instead of being a just a flat circle they were cast with a wave style. That way we got more surface area to help cool but let us keep the solid rotor.

What it breaks down to is surface area
So what is the best way to loose heat? More surface area. Think of the cooling fins on a cylinder or diff cover or what ever. You want to give the most air you can to the most surface area. What will cool better a solid rotor that is only allowed to dissipate heat from the out side surface only or one that is drilled allowing more surface area for the air to cool the rotor underneath the braking surface. if that makes since.
 

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I ❤ BOOBIES
MY16 Impreza Sport Limited
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Quote:
Originally Posted by teeceRS
So if they're only on there for looks, does that mean they're not really drilled? Because i'm quite sure they are drilled all the way through, and whether they're there for looks or not if your theory is right then NW OBS is also right in saying that according to your theory many of the daily driver built high end vehicles with drilled rotors are also unsafe.

The only reason high end performance cars have drilled rotors are for lighter rotors and looks. Plus, most of these cars have huge rotors. I am sure NW OBS does not have the same rotor size on his Subaru that these cars have. Most of the people that buy the high end cars can afford to replace their rotors every 6 months before they start cracking.
Ok, that makes more sense and clears up my question. Thank you.

We don't need pictures of your drilled rotors, there are going to be drilled rotors that don't crack. It all depends on how hard you drive on them, how big the rotor is, etc. The entire point is that they do not benefit over blank rotors except for weight loss.
EXACTLY why there is no reason why NW OBS shouldn't have drilled rotors because he obv isn't using a tiny set of factory sized drilled rotors. Most upgrade-able rotors are increased in diameter. And also, you just said it yourself, it depends how you drive on them, so for someone to drive on them as a dd which means no extreme wear and tear it doesn't sound completely impractical for his uses.

i say we just do 4 wheel drums! hahahaha
 

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i as well have tracked and auto crossed my car. The time that the car is on an autox course is what 60 to 120 seconds at a time, hitting minimal speeds compared to the track, and minimal braking needed.

in my experience, i have done two full track days (running 4 1/2 hour sessions each day and two autox sessions), and im still on the same rotors and pads for 3 years now.... as with some of my friends who are on blanks and lost 50% of their pads alone on one track day. coincidence ?
haha wow

when in reality this could be

a) they are better drivers, reaching faster speeds, and dont coast, theoretically your car should either be braking or accelerating at any given point

b) you are a better driver, and dont brake as much as they did (see my previous auto-cross/track driving post)

c) they drag their brakes for no reason due to inexperience

ive known guys to blow through a set of pads in a single weekend, they also tend to win their classes because they have no fear going into a corner at 180kph, trail braking through the entire thing.

your argument saying that blanks eat rotors is ridiculous, i cant even believe i'm bothering to respond.
 

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ok I am going to throw a little motocross reasoning at you guys here. I am not sure how many of you follow motocross but I raced amateur nationals for many years and although I dont race anymore (broken back) I still wrench for many of my friends. Bikes see more brake abuse that almost anything. Back in the early two thousands slotted rotors were the way to go to keep thing light. That is what came stock on them and everyone used them except for mud races. We found that mud and grime would get in the slots and have a very adverse effect on bad life and and braking (small amounts of mud making its way between pads and rotors in between brake applications). We started running solid rotors to combat the grime problem but experienced worse brake faded (not cooling well enough). The solution? Wave rotors. Instead of being a just a flat circle they were cast with a wave style. That way we got more surface area to help cool but let us keep the solid rotor.

What it breaks down to is surface area
So what is the best way to loose heat? More surface area. Think of the cooling fins on a cylinder or diff cover or what ever. You want to give the most air you can to the most surface area. What will cool better a solid rotor that is only allowed to dissipate heat from the out side surface only or one that is drilled allowing more surface area for the air to cool the rotor underneath the braking surface. if that makes since.
but many front rotors and some rear rotors (on better cars) have cooling ducts inside that go almost to the center of the brake disk
 

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but many front rotors and some rear rotors (on better cars) have cooling ducts inside that go almost to the center of the brake disk
while yes that is true...still the more surface area the better. A choice must be made also...where does to much cooling area have a negative effect on braking area. I brought up the solid rotors and mud because you pointed out the wrc cars
 

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Those are slotted rotors... doesn't that negate the point you have been trying to get across?
actually my point is that you dont need fancy rotors,

and if you would pay attention to the video, the tech talks about rotor size and calipers more than he does about dinky little holes drilled into the rotor

he never even mentions the little slots, just the raw size of the damn thing in relationship to what the intended application is

ergo my original point, that for the street, slotted + drilled + 400mm + 10/10 pots + quadruple brake lines + mad yo' sticker = dont mean crap when the car next to you with single pots stops just the fucking same, and could probably stop better if it did not have balding all seasons and a 4 year old brake pad.

this extends a good portion on to light track duty as well, i have many friends who track on OEM sized brakes and calipers with nothing more than good pads and high temperature brake fluid, with success.

what is sad is that no one that does 20 lap door to door racing has chimed in yet...
 

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actually my point is that you dont need fancy rotors,

and if you would pay attention to the video, the tech talks about rotor size and calipers more than he does about dinky little holes drilled into the rotor

he never even mentions the little slots, just the raw size of the damn thing in relationship to what the intended application is

ergo my original point, that for the street, slotted + drilled + 400mm + 10/10 pots + quadruple brake lines + mad yo' sticker = dont mean crap when the car next to you with single pots stops just the fucking same, and could probably stop better if it did not have balding all seasons and a 4 year old brake pad.

this extends a good portion on to light track duty as well, i have many friends who track on OEM sized brakes and calipers with nothing more than good pads and high temperature brake fluid, with success.

what is sad is that no one that does 20 lap door to door racing has chimed in yet...
and I doubt many on this forum will....
 
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