BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Track / Autocross / Dragstrip / Driving Techniques
 
Post Reply
 
Thread Tools Search this Thread
      06-01-2012, 09:02 AM   #1
besiktas
Ultimate Driver for the Ultimate Driving Machine
 
Drives: BMW M3 E92
Join Date: Oct 2009
Location: Houston, TX

Posts: 973
iTrader: (0)

How to avoid warping stock rotors at track?

Ok, the one way to answer this is to be more conservative at track. My question is, if i have higher quality brake pads, would it prevent damaging my rotors? or regardless of the brake pads the rotors will get damaged as they dont handle heat well either?

I am thinking of investing some $$$ on higher quality brake pads but if they are still going to cause my rotors to go bad, then i might not.

Thanks
__________________

BMW M3 E92 - Silverstone II
BPM Sport Stage II Tune + Test Pipes, GTS DCT Tune
besiktas is offline   United_States
0
Reply With Quote
      06-01-2012, 09:09 AM   #2
Gearhead999s
Major General
 
Gearhead999s's Avatar
 
Drives: E93 335is(wifes)E92 M3
Join Date: Apr 2007
Location: Toronto

Posts: 6,677
iTrader: (0)

Your rotors do not warp at the track but it is uneven pad deposits that cause the pedal pulsation.Proper track pads such as Pagid RS 29's and a proper cool down lap before entering to pits will go a long way to eliminating this problem.

http://www.stoptech.com/technical-su...nd-other-myths
Gearhead999s is offline  
0
Reply With Quote
      06-01-2012, 09:11 AM   #3
LiM3y
Major
 
LiM3y's Avatar
 
Drives: 2008 E90 M3
Join Date: Jun 2009
Location: CT

Posts: 1,201
iTrader: (2)

You might be suffering from uneven pad deposit (search this). It is tough to warp the stock M3 rotors, but easy to overwhelm the street pads. During press release days for the E9X M3, BMW installed ceramic pads in the stock car.

This happens to all novices transitioning to intermediate and indicates time to switch pads and brake fluid to higher spec racing fluid for track days. Braided steel lines help too.

[Gearhead beat me too this]
__________________
LiM3y is offline   United Kingdom
0
Reply With Quote
      06-01-2012, 09:16 AM   #4
CanAutM3
Brigadier General
 
CanAutM3's Avatar
 
Drives: 2008 E92 M3 (2015 M4 on order)
Join Date: Jan 2012
Location: Montreal

Posts: 3,420
iTrader: (0)

Garage List
2008 BMW M3  [0.00]
2006 Audi S4  [0.00]
Quote:
Originally Posted by Gearhead999s View Post
Your rotors do not warp at the track but it is uneven pad deposits that cause the pedal pulsation.Proper track pads such as Pagid RS 29's and a proper cool down lap before entering to pits will go a long way to eliminating this problem.

http://www.stoptech.com/technical-su...nd-other-myths
+1 ^^ This

The M3 rotors are pretty robust.

Last edited by CanAutM3; 06-01-2012 at 11:39 AM.
CanAutM3 is offline   Canada
0
Reply With Quote
      06-01-2012, 09:45 AM   #5
apecush
Lieutenant
 
Drives: 2008 E90 M3
Join Date: Aug 2011
Location: Edmonton

Posts: 430
iTrader: (2)

Another good way to prevent the "warped" feeling is after the cool down lap, do not come to a stop and hold the brakes or engage the emergency brake in the pits. If you have to, have a piece of wood to stop the car from rolling. Holding the car with the brakes on is a great way to deposit pad material onto hot rotors.
apecush is offline  
0
Reply With Quote
      06-01-2012, 10:07 AM   #6
OC3
Havin' a blast!
 
OC3's Avatar
 
Drives: 2013 M3 E92 Jerez Blk DCT ZCP
Join Date: Nov 2010
Location: SoCal

Posts: 4,638
iTrader: (0)

Also, if the session turns into an extended one (i.e. more laps than the usual), try to run a cool-down lap or two somewhere during the session.
__________________

BRP CW13 1:58 | CVR CW 2:01 | CVR CCW 2:02 | ACS 1:53 | WSIR 1:34
2013 E92 M3 Jerez Black DCT ZCP | JRZ RS Pro | Brembo BBK | Endless ME20 | Volk TE37 18x10.5 squared | NT01/TD
OC3 is offline   United_States
0
Reply With Quote
      06-01-2012, 04:17 PM   #7
Bbenavitz
New Member
 
Bbenavitz's Avatar
 
Drives: BMW m3
Join Date: Jun 2011
Location: Naples

Posts: 25
iTrader: (0)

It is interesting all these sources tell you it is nothing more than a build up or deposit of pad material, but if you have your rotors turned to true them the lathe operator will show you the metal being removed to bring the run out down to acceptable levels. It is definately not pad material being removed, because if it was your rotor thickness would not be sustantially reduced they way it is to get a true rotor. Since I first started seriously tracking cars in 1989 using stock rotors and race pads I have found that every car since then (Mazda RX2 race car, Acura Integra R, C5 Corvette, Mitsubishi Evo 8, C6 Z06, and now the M3) all will produce a warped rotor after 4 to 6 one day track events, assuming you are pushing hard enough to get a lot of heat into the braking system. In my opinion rotors are consumable items when tracking your M3 just like the pads, brake fluid, and tires are.
__________________
2011 M3 Sedan
ZCP, DCT
Dinan tune, intake, pulley
265-35-19 Hoosier R6's
for the track with Carbotech pads
Bbenavitz is offline  
0
Reply With Quote
      06-01-2012, 04:18 PM   #8
tibra1
Banned
 
Drives: 2011 ZCP M3 - 2007 335i crashd
Join Date: Apr 2009
Location: NYC

Posts: 6,777
iTrader: (4)

Quote:
Originally Posted by Gearhead999s View Post
Your rotors do not warp at the track but it is uneven pad deposits that cause the pedal pulsation.Proper track pads such as Pagid RS 29's and a proper cool down lap before entering to pits will go a long way to eliminating this problem.

http://www.stoptech.com/technical-su...nd-other-myths
^This..warping rotors is not as common as most people think..most of time fault lies with the pads
tibra1 is offline   No_Country
0
Reply With Quote
      06-01-2012, 05:48 PM   #9
Gearhead999s
Major General
 
Gearhead999s's Avatar
 
Drives: E93 335is(wifes)E92 M3
Join Date: Apr 2007
Location: Toronto

Posts: 6,677
iTrader: (0)

Quote:
Originally Posted by Bbenavitz View Post
It is interesting all these sources tell you it is nothing more than a build up or deposit of pad material, but if you have your rotors turned to true them the lathe operator will show you the metal being removed to bring the run out down to acceptable levels. It is definately not pad material being removed, because if it was your rotor thickness would not be sustantially reduced they way it is to get a true rotor. Since I first started seriously tracking cars in 1989 using stock rotors and race pads I have found that every car since then (Mazda RX2 race car, Acura Integra R, C5 Corvette, Mitsubishi Evo 8, C6 Z06, and now the M3) all will produce a warped rotor after 4 to 6 one day track events, assuming you are pushing hard enough to get a lot of heat into the braking system. In my opinion rotors are consumable items when tracking your M3 just like the pads, brake fluid, and tires are.
I use to have issues with cementite when using heavy metallic pads but never with the newer type pads. and when you try to cut them with a brake lathe the bit will start to chatter and will not cut properly and then the best solution is to replace the disc.90 % of the time rebedding the brakes will clean up the pad deposits.On my previous E92 M3 ran 3 years with about 40 track days on the original standard rotors with no issues.

[quote]The only fix for extensive uneven deposits involves dismounting the discs and having them Blanchard ground - not expensive, but inconvenient at best. A newly ground disc will require the same sort of bedding in process as a new disc. The trouble with this procedure is that if the grinding does not remove all of the cementite inclusions, as the disc wears the hard cementite will stand proud of the relatively soft disc and the thermal spiral starts over again. Unfortunately, the cementite is invisible to the naked eye./QUOTE]
Gearhead999s is offline  
0
Reply With Quote
      06-04-2012, 08:24 PM   #10
besiktas
Ultimate Driver for the Ultimate Driving Machine
 
Drives: BMW M3 E92
Join Date: Oct 2009
Location: Houston, TX

Posts: 973
iTrader: (0)

Great link, thanks.

Quote:
Originally Posted by Gearhead999s View Post
Your rotors do not warp at the track but it is uneven pad deposits that cause the pedal pulsation.Proper track pads such as Pagid RS 29's and a proper cool down lap before entering to pits will go a long way to eliminating this problem.

http://www.stoptech.com/technical-su...nd-other-myths
__________________

BMW M3 E92 - Silverstone II
BPM Sport Stage II Tune + Test Pipes, GTS DCT Tune
besiktas is offline   United_States
0
Reply With Quote
      06-04-2012, 10:06 PM   #11
admranger
First Lieutenant
 
admranger's Avatar
 
Drives: 2002 M3, 2005 X5, 2011 M3
Join Date: May 2011
Location: Las Vegas

Posts: 348
iTrader: (0)

Quote:
Originally Posted by Bbenavitz View Post
It is interesting all these sources tell you it is nothing more than a build up or deposit of pad material, but if you have your rotors turned to true them the lathe operator will show you the metal being removed to bring the run out down to acceptable levels. It is definately not pad material being removed, because if it was your rotor thickness would not be sustantially reduced they way it is to get a true rotor. Since I first started seriously tracking cars in 1989 using stock rotors and race pads I have found that every car since then (Mazda RX2 race car, Acura Integra R, C5 Corvette, Mitsubishi Evo 8, C6 Z06, and now the M3) all will produce a warped rotor after 4 to 6 one day track events, assuming you are pushing hard enough to get a lot of heat into the braking system. In my opinion rotors are consumable items when tracking your M3 just like the pads, brake fluid, and tires are.
Funny... I did not warp one rotor in 6 years of driving schools and 10+ years of racing (and instructing) and I had terrible technique for a number of years -- way too late and way too hard -- great way to build up heat. Add in that for many years the car was a two driver car and you have the recipe for warped rotors. All brakes were stock but the pads were not, they were always race pads. Started with PF90s, used Hawk HT-14 and HT10s, PF01s, and now since I'm retired I run PF06's. PF08's will go on the car next. For the street I use PFC Z-rated pads so there is no need for bedding between the different pads as I swap them. Plug and play. No. I don't work for PFC nor do I have a financial interest in anyone who sells PFC pads (wish I did).

Stock pads on the track will produce pad deposits as I found out at the Salzburgring in 2002 with a new M3. Switched to Hawk pads since I had three more tracks to run (A-1 ring, both tracks at the Nurburgring) and no problems. Those in the group that didn't switch rotors, including some uber fast racers (National champion w/years of ring experience is one example) did have pad deposits even when being careful.

A great way to remove stock pad deposits is to put on a set of aggressive race pads and do some street driving with them. That'll machine a bit off the rotors in no time!

OP: Get some good track pads for your DE events and enjoy your car.
__________________
'11 E90 M3, Mebourne/Black/Fox Red/Black, 6MT, PP2, heated seats, moonroof, split folding rear seats, iPod/USB adapter, Technic harness, JL XD 6/600.
'02 E46M3, Imola/Black, 6MT, CWP, no sunroof, Ohlins, Eibachs, PFC DD rotors, PFC pads! HAT Clarus/Legatia speakers, 2 big amps in the back.
'05 X5 4.4i, Imola/Black, Premium, Cold, HAT Imagine 6.5's, Intravee iPod adapter
admranger is offline  
0
Reply With Quote
      06-05-2012, 02:10 PM   #12
llis
octane chick
 
llis's Avatar
 
Drives: Ms
Join Date: Oct 2010
Location: Colorado

Posts: 1,125
iTrader: (1)

Garage List
2003 BMW M5  [0.00]
2002 BMW 530i (fs)  [0.00]
2013 BMW M3  [5.00]
I don't track my E92 M3 anymore (got an E36 racecar), but never had a problem with rotors. OEM rotors are actually pretty darned good quality already. Occasional judder can be from deposits, as others have noted.

Your pads are more likely to fail under track stresses than your rotors. Pads can melt, split, suddenly chunk, and before you know it you have stopping problems and a 4-figure maintenance repair.

Hawk DTC-70s are awesome pads for our heavy beasts, and they are very kind to the rotors and sustain high heat extremely well. (And you can keep them on the car throughout the season, as long as you don't mind the dying cat sound as you approach every stop on the street. Or swap them just for track weekends.) If the 70s aren't doing it, next step would be a BBK kit to get more volume to absorb all that friction heat. That's what I'd do if I were tracking more than the occasional DE weekend.
__________________

2013 E92 ///M3 ZCP 6MT Speed Yellow 2003 E39 ///M5
llis is offline   United_States
0
Reply With Quote
      06-05-2012, 02:15 PM   #13
Malek@MRF
BimmerPost Supporting Vendor

 
Malek@MRF's Avatar
 
Drives: E92 M3
Join Date: Jan 2008
Location: Irvine, California

Posts: 3,327
iTrader: (5)

Send a message via AIM to Malek@MRF
Hawk DTC-70's paired with the factory rotors along with decent fluid and SS lines are a great combination.

I have managed to warp the two front rotors on the E9x M3 at the track. It was 95* out and after about 7 sessions on stock pads. A little bit of machining on the lathe took care of it and they were as good as new again with plenty of rotor thickness remaining.
__________________

BMW PERFORMANCE SPECIALISTS. Suspension. Forced Induction. Brakes. Race Preparation. Service. Alignments.
OFFICIAL PARTNERS: Öhlins. KW Suspension. Brembo. AP Racing. ESS Tuning. iND Distribution. Turner Motorsport.

Facebook | Instagram | Yelp! | Flikr | Contact | YouTube
Malek@MRF is offline   United_States
0
Reply With Quote
Post Reply

Bookmarks

Tags
brake pads, rotors

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 03:32 AM.




m3post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST