New Record for Cracking Rotors

[DrumrBoy]

45 minutes. No sh*t.

Brand new rotors, brand new Hawk pads, bedded properly....only ran 3 sessions (15 minutes each) at Road Atlanta last weekend before this happened.

Since my last post on this subject (when I was frustrated about getting only 2 weekends out of a set of cryo-treated rotors!) I added the porsche-style air deflectors to dorect some air to 'em....but it didn't seem to do much at all. Temps were in the high 40's which if there was ANY air flow, should have been decent for cooling.

These rotors clearly ****. They are EBC and have those nice little dimples which, as you can see, provide a nice crack propagation point. However, even crappy rotors should last longer than this, right?

Here are some pix....(and yes, I changed rotors as soon as they cracked).

Do any of you guys who do road courses have any pix of the ducting systems you use/ Jon B, do you have any pix of the systems you sell? This is really ******* me off....I should get more than 45 minutes out of a set of rotors....

 

[RedEnuf93]

That *****.....

I use the drilled ones only on street (Bling-Bling) and the stock ones at the track.
So far that combo has worked fine. (and yes, I change the slotted rotors once a year, worn or not.)

 

[AZTVR]

These rotors clearly ****. They are EBC and have those nice little dimples which, as you can see, provide a nice crack propagation point. However, even crappy rotors should last longer than this, right?

I don't know whether EBC intended those rotors to withstand track use, or whether they are for street "bling" only.

I guess that I would only use rotors that have a proven "track" record on the track.

 

[luc]

Nothing surprising with after-market cross drilled rotors. They are only for show and light duty driving, certainly not for open track or racing.
What a lot of peoples don't realize is that the drilled rotors that come from the factory on some cars, ( Porshe, Ferrari, etc) are CAST with the holes, not drilled afterward and use a much better metal that your typical cheap cross-drilled after market rotors.
Stick with a good brand of slotted rotors and you will be fine.

 

[michaelnouri]

chinese iron, try brembo two piece, italian rotors rule.

 

[DrumrBoy]

Comments about drilled rotors for street are spot on.... these were supposed to be slotted only - but I got drilled ones probably by mistake. I goofed by not opening the box until the morning of the event....so i put 'em on anyway.

I have had non-Chinese iron sent out for slotting and cryo treating and that lasted a few weekends, but at $500/pair i was looking for a slightly more economical alternative.

I haven't tried the brembo 2-piece though I have the hats for 'em. so I'm halfway home. Do the Brembo slotted 2-piece units truly hold up to heat better? hey're expensive for sure, don;t mind paying the price if they last better than stock.

 

[michaelnouri]

when i was in germany, most of the track guys and all the european crowd, don' touch baer or stoptechs for any cars.
the brembo are expensive but well proven and worth every dollars, once you own a pair you can buy the disc pretty reasonable, i have one set of hats, and two sets of discs/rotors in stock.
when slotted failure rate is low.
most people are buying rotors for looks and cost makes up most decisions on purchases.

 

[Marv S]

Have you seen Cone's brake duct for Gen 2:

http://forums.viperclub.org/rt-10-gts-discussions/534984-cones-brake-ducting-kit.html

http://forums.viperclub.org/new-pro...buys/548594-debut-cone-brake-cooling-kit.html

http://forums.viperclub.org/new-pro...buys/548594-debut-cone-brake-cooling-kit.html

 

[1994viper]

Could it be that the rotors were defective initially? I clearly see that the holes are not drilled completely through. I also have drilled and slotted rotors on all of my cars for many years. I have never seen anything like that. Though I remember a while back someone mentioned to me to keep an eye on those drilled holes, and clean them periodically as they get plugged with brake dust and rotor overheats.

 

[DrumrBoy]

Have you seen Cone's brake duct for Gen 2:

http://forums.viperclub.org/rt-10-gts-discussions/534984-cones-brake-ducting-kit.html

http://forums.viperclub.org/new-pro...buys/548594-debut-cone-brake-cooling-kit.html

i followed the link but the pix musta been old...they didn't show up. I'll check other sites for pix. Thx

 

[RevHeat]

I just bought a set of these exact rotors from JonB and ran them at Texas World Speedway last weekend with no problems. According to Jon, the EBC rotors can withstand track days with a proven record.

I noted that you were running Hawk pads and I have EBC Red on mine. I am not sure if pads would make that big of a difference, but it might have been a possbile caused. Or as someone commented, I wonder if there was a defect for that rotor.

I would like to hear Jon weigh in as he sells lots of EBC rotors.

Chris Green

 

[3SRTsandGTS]

I have the same EBC rotors on my 98 GTS, and track this car at a 0.6 mile course that requires severe braking numerous times (no brake cooling vents installed). I've had the same rotors for about 15 events without any problems. I am using BrakeMan 3 pads (keep these rotors and pads on the car for the street as well). Can you elaborate on what Hawk Pads you use? I've see Hawk Blues and Black cause severe cracking.

My '06 race-prepared car (SCCA T1 car) uses the comp. coupe brake ducts. I run stock rotors and they last the entire year (9-10 races). They could not withstand an 11th event, but I am impressed they hold up so well.

 

[mjorgensen Woodhouse]

What has probably happened with these is that you are directing cool air at the inner face of the rotor only. This causes a disparity in the cooling of the rotor. They (inner and outer faces) cool at a different rate and the balance of expansion and contraction will cause this to happen. If you are adding brake ducting it should ALWAYS be directed to the center of the rotor hub so it pumps out through the center rather than trying to cool the surfaces of the rotors.

FYI

 

[Tom F&L GoR]

If you research the history and development of brake pads and rotors, you'll learn that slots and holes were introduced when brake pad technology was pretty poor for racing. The slots and holes were needed to clean the pad face, not to vent or cool the rotor. The old brake pads were only effective at stopping within a smaller temperature range than today's pads, so dust, gas build-up, glazing, etc was a big deal. Modern pads don't really need slots or holes, although now slots and holes are added to reduce rotor weight. All this background explains to me why OEM rotors aren't such a bad choice.

 

[FrankBarba]

the air deflectors are junk. when i was racing my other viper i just ran the standard viper rotors they worked fine.

 

[AZTVR]

the air deflectors are junk.

Which air deflectors are you referring to ?

 

[Chuck 98 RT/10]

I will never track anything less than a two-piece rotor. It isn't that a one-piece can't do the job but if a manufacturer builds a two-piece rotor then I know they are serious about racing and will most likely put more quality into their product.

And a two-piece rotor will have cooling vanes instead of pegs like below...

 

[Camfab]

Why would'nt you just use stock rotors? This just another shinning example of why you should stick with factory parts.

I think people should reconsider their "mods Lists" my upgrades should probably read.........how I downgraded my GTS.........Slotted/Dimpled Chinese Pep Boys Rotors, Aluminum Radiator, Lightweight Aluminum flywheel with super bitchin non marcel six hockey puck clutch, Coated big tube headers with no heat shields cause the factory does'nt know what they are doing, 100mm throttle bodies cause you just can't make'em big enuff....................................

 

[Fatboy 18]

Just posted a link to this thred over on the UK site, I know a lot of the guys run these rotors

 

[FrankBarba]

Which air deflectors are you referring to ?

Porsche Air Deflectors. they are great ground scrapers.

 

[FrankBarba]

if you are really intersted in cooling down your rotors, you will need to grab a set of comp coupe brake rotor cooling kit & run your tubes from the front of the facia or try the Cone Set up. Jon B should know where to get the Cone set up...

 

[dave6666]

Why would'nt you just use stock rotors? This just another shinning example of why you should stick with factory parts.

I think people should reconsider their "mods Lists" my upgrades should probably read.........how I downgraded my GTS.........Slotted/Dimpled Chinese Pep Boys Rotors, Aluminum Radiator, Lightweight Aluminum flywheel with super bitchin non marcel six hockey puck clutch, Coated big tube headers with no heat shields cause the factory does'nt know what they are doing, 100mm throttle bodies cause you just can't make'em big enuff....................................

Just wanted to tell the world that I've upgraded to the factory radiator. But I balanced the downgrade of the headers with my killer custom heat shields.

 

[DrumrBoy]

I have the same EBC rotors on my 98 GTS, and track this car at a 0.6 mile course that requires severe braking numerous times (no brake cooling vents installed). I've had the same rotors for about 15 events without any problems. I am using BrakeMan 3 pads (keep these rotors and pads on the car for the street as well). Can you elaborate on what Hawk Pads you use? I've see Hawk Blues and Black cause severe cracking.

My '06 race-prepared car (SCCA T1 car) uses the comp. coupe brake ducts. I run stock rotors and they last the entire year (9-10 races). They could not withstand an 11th event, but I am impressed they hold up so well.

I'm using Hawk Blue pads. They're tough on rotors, but typically the toughness manifests itself in heavy wear. Perhaps the pads are a contributor to the cracking problem, but I'm guessing i have some cooling issues to address as well.

 

[DrumrBoy]

What has probably happened with these is that you are directing cool air at the inner face of the rotor only. This causes a disparity in the cooling of the rotor. They (inner and outer faces) cool at a different rate and the balance of expansion and contraction will cause this to happen. If you are adding brake ducting it should ALWAYS be directed to the center of the rotor hub so it pumps out through the center rather than trying to cool the surfaces of the rotors.

FYI

This is true. The Porsche air deflectors (which i think are relatively worthless....I was just seeing if they made a difference) direct air generally at the inside of the rotor...not specifically to the center. Net net, though, I don't think they did more than scrape the ground alot - I wouldn't recommend 'em.

 

[DrumrBoy]

If you research the history and development of brake pads and rotors, you'll learn that slots and holes were introduced when brake pad technology was pretty poor for racing. The slots and holes were needed to clean the pad face, not to vent or cool the rotor. The old brake pads were only effective at stopping within a smaller temperature range than today's pads, so dust, gas build-up, glazing, etc was a big deal. Modern pads don't really need slots or holes, although now slots and holes are added to reduce rotor weight. All this background explains to me why OEM rotors aren't such a bad choice.

My best results to date have been with cryo-treated OEM rotors. I get 3-4 weekends out of em. I thought I should get better life out of 'em so I'm changing things (not scientifically enough though) ....pads....rotors...cooling systems....to see if I can get to the 10-11 race results described earlier.

Next I'll try non-treated OEMs and see how long they go.

I agree, drilling and dimpling is just bling, cool for the street but a downside for extreme applications.

 

[DrumrBoy]

Why would'nt you just use stock rotors? This just another shinning example of why you should stick with factory parts.

I think people should reconsider their "mods Lists" my upgrades should probably read.........how I downgraded my GTS.........Slotted/Dimpled Chinese Pep Boys Rotors, Aluminum Radiator, Lightweight Aluminum flywheel with super bitchin non marcel six hockey puck clutch, Coated big tube headers with no heat shields cause the factory does'nt know what they are doing, 100mm throttle bodies cause you just can't make'em big enuff....................................

I've used alot of stock rotors, cryo'd and not. I'm searching for the best combination for performance and life. So far cryo-treated OEM wins, but on my car the life is still unacceptable.

Are you suggesting that we all just stick with the OEM solution for everything. I guess I should lose the headers, and 1.7 rockers. Anybody got a set of heads that flows 220? I'll trade you even for my 300 CFM heads. I guess I won't need those big throttle bodies and, come to think of it, if anybody needs an AEM I'll trade you even for a stock PCM.....

 

[AZTVR]

I have the same EBC rotors on my 98 GTS, and track this car at a 0.6 mile course that requires severe braking numerous times (no brake cooling vents installed). I've had the same rotors for about 15 events without any problems. I am using BrakeMan 3 pads (keep these rotors and pads on the car for the street as well). Can you elaborate on what Hawk Pads you use? I've see Hawk Blues and Black cause severe cracking.

What has probably happened with these is that you are directing cool air at the inner face of the rotor only. This causes a disparity in the cooling of the rotor. They (inner and outer faces) cool at a different rate and the balance of expansion and contraction will cause this to happen. If you are adding brake ducting it should ALWAYS be directed to the center of the rotor hub so it pumps out through the center rather than trying to cool the surfaces of the rotors.

The Porsche air deflectors direct air generally at the inside of the rotor...not specifically to the center. Net net, though, I don't think they did more than scrape the ground alot - I wouldn't recommend 'em.

So, to summarize, it sounds to me like the EBC slotted and dimpled rotors are up to HPDE track days for some levels of driver and track. I'd guess that DrumrBoy is doing some very high speed braking which probably results in higher temps than a tight, short track. Add in the differential cooling from some air deflectors and some very aggressive pads, and we have found the limitations of this product.

It does show why manufacturers do not warrant or market their aftermarket products for racing purpose unless they were designed for it.

 

[AZTVR]

.........Slotted/Dimpled Chinese Pep Boys Rotors, ....................................

Your reference above in this thread may be misleading although it may have been unintended. I certainly agree that we should not support Chinese manufactured products, if that's what they are.

From EBC's website:
"Premium quality EBC brake pads and rotors for cars, trucks, motorcycles, is our business .... all made in the UK."

"The motto at EBC Brakes and EFI is NOT to import any brake product from third world countries and to manufacture every piece possible in its own facilities."


I can understand why reputable manufacturers and vendors cringe when they read threads like these.

 

[Grant]

And a two-piece rotor will have cooling vanes instead of pegs like below...

Most 1-piece rotors have vanes as well. Hell, the $25 rotors on my C5 have directional vanes. I wouldn't run the rotors in the pic in my dog's lawnmower.

 

[mjorgensen Woodhouse]

I have access to the Comp Coupe brake duct kit and can help you get it. They are $450is and are carbon. Definitely worth the price though for correct cooling.