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      09-18-2015, 09:06 PM   #1
horsepower_and_hounds
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Help advise on brake rotors M235i

So i am in the market for some bling and rotors is it's name. Help me deside what is about the best for a daily driver and spirited week end runner. WIll be running low dust semi metalics

So which one?

High carbon cross drilled
High carbon slotted
High carbon dimpled & slotted

Cannot get drilled and slotted.....

I do not know how to set up a poll
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      09-20-2015, 10:26 PM   #2
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If you plan on driving hard at all don't get anything but slotted. The drilled or drill/slotted will crack from the heat.
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      09-21-2015, 09:44 AM   #3
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Quote:
Originally Posted by SteveInfante View Post
If you plan on driving hard at all don't get anything but slotted. The drilled or drill/slotted will crack from the heat.
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      09-22-2015, 05:02 AM   #4
horsepower_and_hounds
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I was thinking drilled only....that is what the M's come with I am pretty sure
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      09-22-2015, 01:25 PM   #5
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Drilled = looks only

Vented & Slotted = true performance

Why do F1 and LMP cars run vented only? Because drilled rotors crack under high temp gradients.
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      09-22-2015, 09:27 PM   #6
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Quote:
Originally Posted by allthatisntnow View Post

Vented & Slotted = true performance

Why do F1 and LMP cars run vented only? Because drilled rotors crack under high temp gradients.

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      09-29-2015, 08:47 PM   #7
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As others have said, if it's for looks then cross drilled is fine. If you're looking for performance than you need regular blank rotors......yes, seriously, blank rotors.
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      09-30-2015, 02:51 PM   #8
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Quote:
Originally Posted by allthatisntnow
Drilled = looks only

Vented & Slotted = true performance

Why do F1 and LMP cars run vented only? Because drilled rotors crack under high temp gradients.
Curious to learn more about this, is the idea behind vented and slotted simply an issue of weight reduction or is there another functional purpose?
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      09-30-2015, 06:59 PM   #9
horsepower_and_hounds
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I am surprised that BMW would spec their top models with drilled rotors if they are not as durable, efficient and overall work better. Maybe peeps just buy M's for the looks

I do not plan on tracking my 235 but am ditching the pads due to all the black brake dust so figured I would ad some rotor bling at the same time
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      09-30-2015, 07:02 PM   #10
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Quote:
Originally Posted by Luminous View Post
Curious to learn more about this, is the idea behind vented and slotted simply an issue of weight reduction or is there another functional purpose?
Vented greatly reduces heat buildup, so that is usually (almost always) a good idea.

Slotted is sort of useful. If you are driving in the rain (or snow), the slots help move water away from the pad. It also (somewhat) helps with heat buildup, but not nearly as much as venting the discs. The effect on the structural integrity of the rotor is much smaller than cross-drilling.

Still, if you are driving your car like an F1 or LMP1, then you just want (I think) blank, vented rotors.
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