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View Full Version : I put some new ebc reds on the front, questions about them



BigKriss
04-12-2005, 09:06 AM
My stock pads where labeled jurid 187. Great pedal feel when cold, not much pedal distance about 2 cm before they bit in. Now it's like 6 cm before the car brakes strongly.

here is my question?

how should the pads behave in term of travel distance and pedal feel.

I took the car to the track with about 70 km of city driving plus 200 km of freeway driving to bed them in. Then I hit the track. I didn't machine the rotors, or use anti squeal material (they don't squeal now). I think I bled the brakes properly. The EBC reds don't fade, but I was getting excessive brake shudder and long pedal feel, even when the pads where warm / hot.

On my 4th session time out there, i began feeling the shuddering. yes i think now they are rotors are warped. The wheels where still very warm 20 mins after a session.

Anyway, besides the rotors taking a beating, what are the symptoms not bleeding the brakes properly?

Even more of a reason now to upgrade the brakes to a 540 package.

Jeff N.
04-12-2005, 09:44 AM
Kris,

- Did you bed in the pads per the instructions? I believe EBC does have instructions on how to heat cycle the pads.

- Re EBC in general - I had a set of EBC Reds and, while they worked great on the street, they did not stand up well to the heat generated on the track. They tended to carbonize and crumble. FYI - this was before I did the cooling upgrades on my brakes. In general, I was not impressed with their lasting ability and that was the last time I used EBC product. I have heard from others similar reports of the Reds not working well on the track.

- Warping of rotors is more likely related to your cooldown procedure than your pads. Are you sure they are warped? Check to see if you have pad compound on the rotor. Since you were using the Reds, I wouldn't be surprised that that's the problem vs actual warping.

- Re wheels still being warm after 20 minutes. Yup. In our past conversations, I advised heat was your enemy and you should really look to get some cooling on your brakes if you plan to do track work.

Jeff

BigKriss
04-12-2005, 09:51 AM
I didn't read the bed in instructions for the EBC reds, i just drove them normally, for about 270km before the track session.

The pads for my session did not fade Jeff, compared to the jurids, they kept on going. also not once did the abs kick in with these pads, however the tyres where making squaling sounds from the deacceration.

are the 540 ducts the way to go or would a DIY option with custom ducting with removal the fog light be more appropriate?

Jeff N.
04-12-2005, 10:01 AM
You should try to follow the heat cycle instructions from the manufacturer. That will ensure maximum pad life and effectiveness.

I'm confused about your no fade, no ABS comment. Do you get ABS lockup early with the Jurids but not later? That could be pad related gassing. If you can always get ABS lockup with the Jurids but not the EBCs, then it sounds like you are getting better bite with Jurids. Describe the fade symptoms better.

The 540 ducts will look stock and seem to work well for me. I never found roter based backing plates for the 5 series. That's a full race setup but would require a high level of fabrication. The 540 ducts look good and you can buy all the parts off the shelf.

Jeff

BigKriss
04-12-2005, 10:24 AM
Sorry Jeff I will try to be more specific.

"I'm confused about your no fade, no ABS comment. Do you get ABS lockup early with the Jurids but not later?"

Yes that is correct. As the jurids wore on I couldn't get ABS lockup. About after 5 hard laps on the jurids, the brakes were not there anymore, extremely spongy however after 7 laps with EBC reds, they where still going strong, no ABS but the front tires where squealing.

I never use my fog lights so I don't car of not having them anymore. I can't tell exactly by your sig pic, but are your ducts underneath the front spoiler or through the fog lights. I'm fearing if I put them underneath the front spoiler, it will be too low too the ground (in terms of hitting low things on the road).

Jeff N.
04-12-2005, 10:45 AM
http://www.bmwe34.net/e34main/upgrade/540_ducts.asp

granit_silber
04-12-2005, 11:53 AM
http://www.bmwe34.net/e34main/upgrade/540_ducts.asp

Jeff,
I am a little confused with the brake ducting on the e34. Hopefully you can help clear it up.

Are the intakes installed on the front spoiler (below foglights) just intakes or is their actually some tube that air flows through to get to the rotors?

If there is no rotor-backing plate, where does the ducted air get directed to?

Thanks,
ashley

Jeff N.
04-12-2005, 12:24 PM
Ashley - the kit will direct air to the top of the caliper. The output of the ducting stops at the forward lip of the front fender well. The ducting "points" the air into the back of the wheel at the top of the caliper.

granit_silber
04-12-2005, 01:19 PM
Ashley - the kit will direct air to the top of the caliper. The output of the ducting stops at the forward lip of the front fender well. The ducting "points" the air into the back of the wheel at the top of the caliper.
Thanks! That clears it up.
-ashley

granit_silber
04-12-2005, 01:26 PM
I never found roter based backing plates for the 5 series.
Jeff

Jeff,

Check out this company. They don't have anything listed for the e34, but maybe they can modify something they have.

http://www.roadracetech.com/performance_catalog/products/cooling.asp

-ashley

Jeff N.
04-12-2005, 01:45 PM
Basically, I don't need it. Also, it's cumbersome to hook up the ducts and expensive to purchase, modify and install.

I'm really happy with my current brake setup. I can drive for 45+ minutes on the track with no degradation. I have sufficient brake torque to meet my needs as well.

Cheers!

Jeff

BigKriss
04-13-2005, 12:21 AM
I didn't realise it was your car was on Bruno's site Jeff.

grave77
04-13-2005, 12:31 AM
check the cooling system made by Bruno, he fit the 540i cooling ducts
http://www.bmwe34.net/e34main/upgrade/540_ducts.asp

I'm considering this very soon since I have the 850i brake system 4 about 2 years and still getting this heat problem.

grave77
04-13-2005, 12:43 AM
Hi Jeff … I have a question here about the brakes. When I brake from high speeds like from 220Km/h down to 90Km/h I hear the sound like a grinder … I thought that’s the ABS, but it also comes when I brake at slow speeds after this heavy one. Is this due to hot disks and calipers? And the vent ducts will solve this problem? I have 850i brakes on the front with the calipers.

Mobius
04-13-2005, 04:20 AM
On my 4th session time out there, i began feeling the shuddering. yes i think now they are rotors are warped. The wheels where still very warm 20 mins after a session.If you follow what is said here (http://www.stoptech.com/whitepapers/warped_rotors_myth.htm) (and I do) - then 'warped' rotors are caused by improper break-in/heat cycling/bedding procedures. If you skipped that, then I think it's pretty likely this is your problem. :\

BigKriss
04-13-2005, 04:38 AM
thanks Mobius, I didn't read that before. What am I to do now?

Interceptor
04-13-2005, 05:42 AM
Hi Jeff … I have a question here about the brakes. When I brake from high speeds like from 220Km/h down to 90Km/h I hear the sound like a grinder … I thought that’s the ABS, but it also comes when I brake at slow speeds after this heavy one. Is this due to hot disks and calipers? And the vent ducts will solve this problem? I have 850i brakes on the front with the calipers.
I get that noise, too, so I guess it's normal. Besides the sound itself, I didn't experience any issues with the brakes.

grave77
04-13-2005, 08:10 AM
so there is nothing wrong with the brake pads nor the Disks ?

Jeff N.
04-13-2005, 08:16 AM
Do you have slotted rotors? My slotted rotors would make sounds like that.

Jeff N.
04-13-2005, 08:25 AM
As the article suggests (as I did as well), your "warpage" is due to pad compound on the rotors. Do you have access to a palm sander? I'd pull the front rotors off and sand them lightly with 100 grit or so. Inspect them for cracks and severe scoring at the same time.

I think you should go to another pad besides the EBC too. I've been using nothing more than PBR metalmasters for track/street use with fine results. $45US for a front pair - cheap. No, they won't quite grab like a set of Porterfield R4 or R4S's but trust me, you don't need that now anyways.

Spend your limited track cash like this:

- stabilize your brakes by finishing your M5 setup, adding some cooling if you want, using the PRB pads, installing some ATE superblue fluid. If you want, you could also add stainless steel brake lines as they flex less due to high heat.

- spend the rest of your money on consumables and track fees. Tires...more tires...tires. And track time.

If you really become a track junkie, you are going to want to get a lighter car with a 5 speed anyways. It will be more fun to drive, have more parts options and use less consumables.

Cheers!

Jeff


thanks Mobius, I didn't read that before. What am I to do now?

BigKriss
04-13-2005, 09:25 AM
thanks jeff, your comments are very much appreciated.

Mobius
04-13-2005, 01:36 PM
thanks Mobius, I didn't read that before. What am I to do now?Yeah - what Jeff said..
Also from the article:

The obvious question now is "is there a "cure" for discs with uneven friction material deposits?" The answer is a conditional yes. If the vibration has just started, the chances are that the temperature has never reached the point where cementite begins to form. In this case, simply fitting a set of good "semi-metallic" pads and using them hard (after bedding) may well remove the deposits and restore the system to normal operation but with upgraded pads. If only a small amount of material has been transferred i.e. if the vibration is just starting, vigorous scrubbing with garnet paper may remove the deposit. As many deposits are not visible, scrub the entire friction surfaces thoroughly. Do not use regular sand paper or emery cloth as the aluminum oxide abrasive material will permeate the cast iron surface and make the condition worse. Do not bead blast or sand blast the discs for the same reason.

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.