Front Rotors

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Tommys 89 635
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Front Rotors

Post by Tommys 89 635 »

Hope everyone is doing well.

Many shops sell cross-drilled & slotted rotors for different prices but not sure about the manufacturers.

Just curious for the folks that are using them, where did you buy your front rotors from?

Any experience from this place ?

https://brakeperformance.com/all-products.php

They’ve got a lifetime warranty on warping and cracking.

Thanks
Tommy
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86_6series
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Re: Front Rotors

Post by 86_6series »

I track my 6 with the big brake upgrade. Several tech guys said better performance and longevity with solid vented.
Don't need drilled and slotted for more secure stopping.
However, if your doing it for looks--well that's another story.
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Re: Front Rotors

Post by bpoliakoff »

Todd Howerton who was in the custom brake caliper business once told me the same and that the drilled and slotted rotors ate brake pads quicker
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Re: Front Rotors

Post by redrumm3 »

A lot of (tuner?) drilled and slotted rotors on the market are drilled and machined after casting, a cheaper method. The proper method is for the slots and holes to be cast into the rotor and then machine finished. Drilling and slotting them afterwards weakens the structure of the rotor and is unsafe. I have seen rotors explode at the track where the cheaper rotors were used.

There are advantages to drilled and slotted rotors, but only in extreme situations like racing applications and yes they are more aggressive on pad wear.

The rear brakes with J-hook rotors on my BMW e92 M3 GT4
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Tommys 89 635
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Re: Front Rotors

Post by Tommys 89 635 »

Thanks for the replies. I don't track my car and yes I am aware of quicker pad wear. As the great Ed Rather told me, they're like a cheese grater.
I've tried many solid rotors (M6, E32 and E34) and they seem to warp so I'm looking for something that would help with heat dissipation. So far the cross drilled has lasted longer than the solids. Any idea would be appreciated, thanks
Tommy
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TBM
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Re: Front Rotors

Post by TBM »

HI Folks,

Drilled was used in yesteryear as brake pads were outgassing and could not make full contact with the rotor at racing temps! That is no longer the case as companies making brake pads have come a long way since. Slotting is there to "clean" the pads as you scrape the pads on the surface while braking. Brake rotors "warp" when they are one piece because they are one piece and can't take the heat in race conditions and have no way to flex.. The two piece rotors are best for racing and spirited driving. What is common in both street and racing is to have the rotors Cryogenically treated. They are 1. stress relieved from the formation process, 2. Increased fine ETA carbides for wear resistance 3. shed heat more quickly due to the refined grain structure that takes place at -315F. I know because I'm in the business and do it regularly for race teams and personal cars alike. We also treat many engine internal components for longevity and high performance output.

If anyone is interested in reading about the process: https://ctpcryogenics.com/services/tran ... on/brakes/
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Re: Front Rotors

Post by BillW »

I helped a friend cross-drill a pair of rotors and the weight difference was noticeable.

For a street-driven car with 5-spoke wheels, I don't need larger, heavier brakes, and I like the cross-drilled look.
And being a e24, I don't see myself regularly abusing the brakes in normal driving.
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LarryM
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Re: Front Rotors

Post by LarryM »

I bought a set of these for the front of my E28. I have about 5K miles on them and they've been great, no complaints.

https://www.tirerack.com/brakes/brakes. ... cat=Rotors
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Tommys 89 635
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Re: Front Rotors

Post by Tommys 89 635 »

Thanks everyone for your comments. I think my likely choice is the e32/e34 drilled & slotted rotors from Stop Tech.

Curious, anyone have any experience with EBC dimpled & slotted rotors?
Tommy
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Re: Front Rotors

Post by jps635 »

I ran a set of ebc dimpled and slotted rotors with red stuff pads for a while in an attempt to improve things as the stock setup is pretty ordinary. They were ok, but nothing spectacular.
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