These are the down fall to this amazing motor. I was traking mine last year with standard pads and discs. These were warping at the end of the pit straight at Knockhill. After some research i have opted for the Zimmerman x-drilled discs all roung and Hawk HP Plus street and ATE super blue. (i would prefer 4 pots, but want to keep the vehicle standard looking)

After one track day evening at Knockhill with 3 20 min sessions this setup never once failed and actually improved the hotter they got. They also work very well on the road as well. If you need an upgraded without having the dosh for 4 pot setup try these.

Happy Braking

I fear you may be in for an unpleasant surprise, fairly soon. Cross drilled disks will eventually crack between the holes. Seen it happen to just about everyone I know who has tried them for track use. The enemy is heat, brake ducting helps big time with the e30 m3. It is the weakest part of the car, but can be made to work fine for track use.

1. Re-build calipers (They must be 10 years old, at least)

2. Run proper brake fluid - SRF, Motul, AP Racing, ATE

3. Use standard BMW supplied EVO Sport disks

4. Use good quality pads - Ferodo, Mintex, Hawk - In semi/race compound

5. Get some ducting to the disks - The bimmerworld kit works very well

6. Stainless hoses

Yeah, can back up lancelotII, cross drilled fronts not recommended. Mine went at the 'Ring, lucky to drop on a set of standard discs so play resumed.

Is there any scarey stories on grooved discs?! Hope not as may have a chance of a gooning day with ones Sport Evo on Groovey discs and pagid fast road pads...

2 years road use no problems, 3 sessions in Oulton Park with Ferodo 2500 and that's the result. I am running Zimmermann plain disks now.

I did look into this and there are manufactures who supplied drilled discs. The holes were drilled after the disc had been manufactured, thus weakening the disc. Zimmermans have the holes cast into the disc when being manufactured.

Also Turner motorsport in the US supply much for autocrossing and they state it the only x-drilled discs they supply as they have bben tested. Anyway I'll see how they go as i only use the car for 5 track days. They was another manufacture i was looking at who treated their discs at higher temps or something to be with the discs handling more heat.

Does anyone know if any 4 pot caliper kits fit with the 16" wheel set up as i want to keep the car standard looking?

215m3,

I have found the same as UweM3, but on other cars, that cross-drilling weakens the disc and makes it far more prone to cracking - Whether or not they are cast into the disc they are still going to be the weakest point.

I also find that the option listed by lancelotII is the best way forward (without going to 4-pots etc.).  On my track 205Mi16 I run quality std. discs with Ferodo DS3000 pads - NO fade, but the downside is alot of dust (with what appears to be a high metal content, so not really suitable for use on the road - They would kill your wheels).

My E30 M3 has drilled discs (on when I bought) which will be replaced soon with std. (once killed @ Knockhill!!).

Regards,

Kev-G.

PS What TrackDays do you do @ Knockhill?  Are you going to the Crail day on 31st May?

Just think they are the standard G88's really... didn't know they came in different materials?

"G88 - High performance disc with 40 grooves machined onto the braking surface. This deglazes the pad and expels gasses that build up between the disc and pad during braking. As a result brake fade is significantly reduced. The slotted disc also dissipates heat more effectively, thus reducing the risk of disc deformation, vibration or cracking under the extreme operating temperature. These discs are ideal for competition use or where fast road conditions allow. "

Kev-G

I am going up to crail on the 31 May, but not tracking.

I track at Knockhill with a chap who organises it mainly for Porsche's, which seem to have x-drilleds as standard, but they don't seem to have cracked from what i've heard. The next event is 28 May starting at 5.30pm with track action from 6pm. Booking is in advance but i think this event is always over subscribed so not sure if there are any spaces. It great to see this car mixing it with the 968 cs's and 964 and 993 through the twisty bits at Knockhill. i popped in too see the last top marques track day but it was just elises and type r's so not the same atmosphere at the one i attend. If you go i am normally the only e30 m3 and is red.

The hawk pads i'm using are fairly high metal pads and keep biting the harder they are pushed. I have all of lancelotII setup bar the discs and ducts, as i'm wanting to keep the standard look.

215m3,

I'm trying to get hold of the guy for the Porsche tracknight @ the moment - See if I can blag a space - I went up last time (a couple of guys from work attend), and was itching to take the BM on (I've done trackdays for 10 yrs. in primarily 205Mi16's) - Finally popped it's cherry @ a Knockhill Season Ticket holders night....:-)

I'm also looking @ going to Crail - Not so sure on that one....

Cheers,

Kev-G

Kev-G

The Guy you need to speak with is Ian Griffiths at Kirby vacuum cleaners in glasgow. yell pages has the number. The lady that answers the phone will know about the track days. It is only limited to 35 cars for each event.

Good luck

Cheers UweM3

Well i've got them on now so will see how long they last. Knockhill is quite hard on brakes so let this be a test. Next track day is on 28 May so will keep an eye on them. The good thing about these track days is their not all day so they only get 1 hours trashing to hell and back in 3 sessions.

I cracked my front Zimmerman cross drilled discs on the street with EBC greenstuff pads. I still got C/D on the back but  as the doing far less braking and are a solid discs too, I guess thats helped.

I got slotted on the fronts with Pagid fast road pads all round as the EBC where pants!!!!

Been  find on the road , but that might all have changed after Monday at Brands!

Ok guys give in. At Knockhill tonight and cracked my front discs(zimmermans), though they took some stick with the Hawk HP plus street pads. What discs should i now put on, bearing in mind i don't have ducts and am not fitting them.

Black Diamonds?

Jonmuirge how are the tarrox's holding up?

Brembos?

The evo sport dics, would they work well without the ducts?

Any others?

Gave the porsche's and ferrari's a run for their money though.

I haven't had my M3 for a month now.. been at PowerStation having some 'stuff' done

I'll le tyou know how the brakes go after my first track day but I've only ever heard great things about G88's on other cars... grooved not drilled so much better than the Zimmermans...

Hi Roops, I have a question for you, and no, I'm not taking the piss or anything!!!

You know how you and quite a few others (like Martin) reckon that big brakes aren't necessary on our cars? (Provided the set up is as good and as thorough as on your car mind you, not just standard E30 M3 brakes). Anyway, if AP Racing approached you and offered you a set of their 4 pot front brakes for free, would you have them then? I'm wondering if you a partly put off by the expense of big brakes you see.

I think there`s no doubt they offer an improvement, probably not in outright braking ability but in braking consistency over a number of laps and less brake disk wear. But it comes down to "do you really need it" at £2000 or whatever, when just brake ducts on a std setup removal some of the advantage large brakes have over std ones. And of course if you take the extra weight of large brakes into consideration and also the fact that you will probably need larger heavier wheels too over the much prefered 15" wheels for track use. Having said that, i prefer the handling on 16`s than 15`s with the 205*55 tyres but have yet to try a 50 tyre on a 15

JW, I would take them free of charge simply to try them out and satisfy my curiosity. I really want to stay on 15" wheels and most of the big brake kits don't give you that option, I just don't have enough horsepower to turn great big 17" wheels. I think it would be a nil gain game. What I would gain in the braking zones I would lose getting the car out of the corners.

I can't think of a time with the optimised standard setup when I have thought "ohhh sh*t, not enough brakes....." I am fairly sure I could get deeper into the braking zones with big brakes and if I was competing I would probably do the big brake thing.

In the end I think it comes down to personal comfort, if the standard setup gives you palpitations every time you get on the brakes then you need to do something with them. As the M3 is now my second car it leaves me a little room to modify it further. I intend to lose loads of weight from it, which will only help in the stopping department.

Roops

I don't think cost is a huge issue for me,

There are options which allow you to retain 15" wheels... but for example with AP this is only possible running with spacers which is not a desired option for many.

The cost is an issue to me in so much as attempting to decide which modifications to the car would give the best relative performance increase per £ (does that make sense)....  i.e with a standard car would I like to spend £1400 on brakes or on bigger cams, or on coilovers etc etc...

I liked the idea of bigger brakes but have to confess I've not found the limit of my standard ones (using ferodo pads) so would rather spend the money elsewhere for now.

I'm no expert but isn't another reason for uprating brakes (aside from braking performance) a consideration of unsprung vehicle weight?

Tom

Tom,

If we are talking about track performance, then a car with well setup suspension will spank far more powerful cars with compromised suspension. Think of it this way. If the maximum speed of your car was only 100mph but you didn't have to slow down for any corners you would drive off into the distance.

I think what your getting at in the unsprung weight department is weight transfer. Heavier cars have greater weight transfer when you step on the anchors, all that energy is turned into heat when the brakes come on. Larger brakes will be able to handle greater quantities of heat as they have a larger surface area (bigger disks) with which to disperse it. Reducing the weight of the car fundamentally has the same effect as fitting larger brake disks. The improvement in reducing braking distances comes from larger pad areas offered by multiple piston calipers.

Roops

Roops

Where did you get the G88? gona give em a try as need to changed them, hopefully for Sunday as off to Keilder, if i can't get them by then i'll get a lift with Gary.

Well it was following our curry house post Brands discussion on suspension that I decided the next job on my car will not be engine based (read Carbon Airbox & Motec or equivalent) but will in fact be Leda/Camber plates.

I recognise that I'm nowhere close to using the power I already (235) have effectively with my current setup...

Increasing track experience will make the biggest difference to my times though methinks.

I'm not sure how much if any difference unsprung weight makes on cars at thislevel, but I understood that lower unsprung weight effectively improved the time (due to momentum) in which the shocks and thus keep the tyres incontact with the road more of the time (huge over-simplification by me I suspect) - call me sad but I find all this stuff quite interesting!

Tom-H

Tom, if you like all that stuff. The book "How to make your car handle" by Fred Puhn is a good read. The technical sections about roll centres, unsprung weight etc. help you understand why certain cars work better than others ie. double wishbone v mcpherson strut.

Roops

Tom,I have a copy if you want to borrow it.

   Jon

Hmm.. please, that would be great, thanks Jon.

I'll get it on the 28th if I don't see you before... thanks again

Hi, just been back from Germany. I have seen some very promising low cost brake solutions to fit 15" rims. Will keep you posted if I have the first test results.

Uwe

Have you checked Gustave's site Tom? There's plenty of great info

http://e30m3performance.com/index.html">http://e30m3performance.com/index.html

TMS do a 4 pot caliper set up that will fit under 15" I believe. They're suppose to be pretty good.

I have been following this thread with some interest as I have shortly to replace mine (pads & disks) I was going to continue with the mintex fast road pads as they have suited my driving up till now (no  track use though - life always manages to get in the way... ) but I was going to go for grooved disks (G88's due to board members experience).

Questions I have are: is it worth getting grooved disks on the rear aswell?

and why are 15" rims favoured? I had noticed that all track prep'd cars tend to run them and again people here seem to prefer them, but I wondered why, as I would have thought that a lower sidewall (as on a 16") would provide less tyre deformation on turn-in etc.  Or have I missed something?

Any answers would be welcome.

Thanks.

4 pots would be great, but would the pressure not create more heat? What discs would be able to handle the extra temps? or am i missing the point? $799 is not bad, but the shipping costs would be another $100 or so, still cheaper than the AP's etc.

Got the G88's to replace the zimmermans so see how these go.

Heres a good site for brakes and the myth of warped discs. 

Lots of good info and could well save you some money on discs because you think tehre warped.

http://www.stoptech.com/technical/">http://www.stoptech.com/technical/

Quote: Originally posted by Houlbt on 04-June-2003

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excellent site Martin.... good find.

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Quote: Originally posted by lancelotII on 13-May-2003

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5. Get some ducting to the disks - The bimmerworld kit works very well

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I now have a F reg M3, when I looked into cooling for the brakes, I was told, Later M3 bumper, new undertray etc etc, in total about £1k.  The kit you have recomended looks like it is quite easy to fit, and as I have witnessed you dissapearing into a red blur at many events, it obviously works well! 

How easy is it too fit, do u have to remove the fog lights etc?

Thanks,

James

James, it's pretty simple to fit. You have to remove the front bumper and remove the fogs. The good thing is that the ducts can use the same mountings as the fogs. You will need to trim the ducts that come from Bimmerworld, I have templates for these that I made when I did mine (I can do copies for anyone who needs them). You also have to cut a hole in the plastic covers that are found on the inside of the wheelarches adjacent to the sump. These let the hoses through. Repalcing the backing plates is very straightforward, 10 minutes with the tin snips sees the old backing plates off. That's it really. If you want to have covers for the ducts to stop birds, small children etc getting stuck in them for daily use I have a wizard and very DTM "Stylie" solution.

Oh, and yes your right, they do work. Probably too well for really cold days. Depending on your pad and ambient temp. running them partly blanked off can be necessary.

Cheers Roops,

That kit does look a good option, I am also looking at another too.  Turner Motorsport (US) do a "four pot" kit that will fit under standard 15" Rims.  The kit comprises of two four pots, and two stainless lines.  They cost $795, which I believe is roughly £500, as to the quality of these or the practicality, that is a different question!  I would've thought the 750 Master cylinder would be a must to drive the fours.

I have other priority's at the moment, I gotta get it going quicker before  a break upgrade is necessary!

Cheers for your help, and I shall see you at Brands!

James