brake rotor quality

[Gurjit]

im on the verge of buying new brakes, front and back
I just installed ecs drilled and slotted rotors with akeenbo ceramics in my brothers 2005 530i
-after bedding them in they perform well. initial bite has decreased slightly but not a big difference. warmed up the brakes are wonderful.
-also installed the S.S. braided lines

ecs also has a kit for my 4.8is for 666$ drilled+slotted or only slotted
-but the price of these rotors scare me
-unlike my brother who drives normally, I drive my suv like a stole it
-multiple +190km/hr brake applications really took a toll on my oem pads

-I believe in the ecs redstuff pads for low dust and higher performance from all the forums and stuff I have read.

-but the low cost of the ecs rotors has me scared. we have all heard of that saying you get what you pay for.
-just cautious of my own safety, as oem's gatta be designed for the beast +250km/hr otherwise bmw wouldn't make the tank move so fast

-I will not buy drilled and slotted for the x5 because of all the cracked rotor hype around drilled brakes

-the oem rotors have not let me down, no vibration, no warpage after 1.5 years of hard driving they lasted me +50,000km
-the pads let me down a couple times, faded on me before and the dust is ridiculous.

front pair= oem blank 333$, brembo blank 230$, ecs slotted/drilled+slotted 195$
rear pair= oem blank 181$, brembo blank 193$, ecs slotted/drilled+slotted 135$

what rotors do you guys have experience with on your x5s?
anyone have tech info on run-outs, metallurgy?

what is the oem brake rotor minimum thickness? the rotors where brand new when I bought the suv off last owner, I wounder if they are designed to wear with the pad or last a pad change

[Brandon002]

IMO.. Drilled and slotted rotors are pointless on a street car. They will wear faster, crack faster and aren't going to give any noticeable performance gain on the street. I think OEM is the way to go on brakes for BMW's... I've tried everything and nothing has the bite under normal driving like OEM.

If you want to spend all that extra cash for brakes that look "racey" more power to you though.

[Gurjit]

Ok so the question is now oem bmw or brembo blanks
Brembo because i save a hole bunch of coin, and i trust brembo to make high quality discs

I will go with ebc red pads for the lessened dust output

[Gurjit]

Originally Posted by Brandon002

IMO.. Drilled and slotted rotors are pointless on a street car. They will wear faster, crack faster and aren't going to give any noticeable performance gain on the street. I think OEM is the way to go on brakes for BMW's... I've tried everything and nothing has the bite under normal driving like OEM.

If you want to spend all that extra cash for brakes that look "racey" more power to you though.

The slotted are half the price of oem

[JCL]

You can often get a second life out of a set of OE rotors with new pads, but why would you if you are concerned about performance? Less thermal mass just means they will fade sooner. Go with new OE.

You ask about rotor specs and metallurgy, but IMO the most important spec is cooling performance, relating to cooling fin design. I wouldn't expect knock off rotors to match OE performance in that respect. And nobody publishes performance specs.

[Gurjit]

Originally Posted by JCL

You can often get a second life out of a set of OE rotors with new pads, but why would you if you are concerned about performance? Less thermal mass just means they will fade sooner. Go with new OE.

You ask about rotor specs and metallurgy, but IMO the most important spec is cooling performance, relating to cooling fin design. I wouldn't expect knock off rotors to match OE performance in that respect. And nobody publishes performance specs.

I agree with your cooling fin insight.

[Isambard]

with Brandon

Originally Posted by Gurjit

Also, how can you be putting 'just cautious of (for*) my own safety' and the fact you drive your suv 'like a(?) stole it' including 'multiple +190km/hr brake applications' taking a toll on oem pads, in the same arena?

I think you've answered your own question here.. -the oem rotors have not let me down, no vibration, no warpage after 1.5 years of hard driving they lasted me +50,000km
-the pads let me down a couple times, faded on me before and the dust is ridiculous. why not just look for other brands of 'higher performance' pads then?

anyone have tech info on run-outs, metallurgy? What metallurgic info are you looking for? how is the data going to make a difference to your choice? if there were major differences between brands you would see that in their prices-and you have already pointed out that it scares you.

[Gary92]

Originally Posted by Gurjit

-multiple +190km/hr brake applications really took a toll on my oem pads

let me guess, hwy 99? that used to be my spot

[StephenVA]

Originally Posted by Brandon002

IMO.. Drilled and slotted rotors are pointless on a street car. They will wear faster, crack faster and aren't going to give any noticeable performance gain on the street. I think OEM is the way to go on brakes for BMW's... I've tried everything and nothing has the bite under normal driving like OEM.

If you want to spend all that extra cash for brakes that look "racey" more power to you though.

Go with OE rotors, some aftermarket pads will provide longer life and a whole lot less dust.
Suggestions:Axxis Deluxe Advanced Ceramic Brake Pads, Power Stop Z16 Evolution Ceramic Brake Pads
Upgrade your rubber brake lines to the calipers to stainless

The options for brake pads are limited as the 4.6 and the 4.8is use BIGGER CALIPERS and rotors than the rest if the x5 models. Theses things are monsters. So no Cool Carbon pads manufactured for us.

Stick with OE if you want cold bite from your pads. Yes, the dust is unbelievable. I think that carbon is the number one element based on the dust created.

[JCL]

Originally Posted by StephenVA

I think that carbon is the number one element based on the dust created.

Truer than many think. Carbon black is used as a filler in the pads, based on its heat conduction, and propensity to reduce squeal. Because of the restrictive TUV specs (which make pad composition changes costly for manufacturers and thus less likely), this means that practically all German vehicles have the same problem.