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View Full Version : Yet another brake thread...


Bzuefishx
02-05-2005, 01:37 AM
OK, I have decided a brake kit is out of the question - lots of other things I'd like to buy for $2,000. Steven has convinced me that big brakes are not a necessity, but I do have some issues:

First - the car pulls to the driver side during high speed braking. My mechanic is a highly experienced BMW guy and says everything looks good, so what gives?

Second - it's hot down here and I do experience brake fade while daily driving (though I do sometimes drive like a jack-ass, it would be nice to have more confidence in my ability to stop).

Third - I'm not all that impressed with the braking distance, especially for such a small car. The brake feel also sucks - I know feel is an intangible, but the rest of the car feels so sporty that I really notice the brakes (have driven several E36 M3's and thought the brakes were much, much better).

So far I've heard the following as lower cost alternatives to a brake kit:

New brake lines - can anyone reccomend a brand and/or type and tell me why?

New pads - can anyone reccomend a decent street/autocross pad that's not too dusty?

Larger brake cylinder - does more fluid mean more pressure and/or smoother pressure? More fluid dissipate heat better?

High performance brake fluid - I've heard the high quality fluids do not heat up as fast - true?

Tune up kit for calipers - to replace worn parts. I assume this means gaskets and/or springs?

Better rotors - My ti's a '98, but has the solid rotors. They are in decent shape, but have almost 50K on them. When they need to be replaced, what should I install and why?

Please forgive my ignorance - I'm a driving enthusiast, not a mechanic. I have a great shop to take the car to, and they usually have good ideas, but wanted to find out what you guys think.

Lastly - I assume I have three options: improve the current braking system, upgrade the system with a brake kit designed to fit my car, or upgrade to M3 brakes, which I understand entails some serious modification to the suspension. Is that it? Are there any other options?

Thanks!

1996 328ti
02-05-2005, 03:16 AM
People generally feel a big improvement when upgrading brakes but it is usually because the fluid is fresh, the pads and rotors are new.

Pads - I use Ultimate Axxis. Ask 12 people their opinion and you may get 12 answers.

Brake fluid - I use Ate.

Rotors - stock 325/328

Stainless steel lines. Some people say you get a firmer feel. Not sure what S/S lines I have in my car but I had Fischer. They are expensive, but I am told they are the best.

I would also rebuild the brakes.

If the car is pulling, it could be one caliper is binding.
Alignment.
Air pressure.

motorsport
02-05-2005, 04:10 AM
first: your car fading to the right, you need to have your slides greased

second: brake fading: your discs may be getting close to spec resulting high temps, so get your discs measured ("mic'ed")

third: braking distance can be effected by glazed rotors and discs, basically the friction surfaces get nice and glossy after being rubbed together thousands of times. if your pads still have 'meat' on them they may just need to be sanded to remove the glossy finish, the rotors can be machined if they are not too thin.

as for s/s lines, im not very experienced on how that can effect your braking performance.

pads i would recommend PBR ceramic pads in the front at least the superior are a step down and are fine for the rear since 70%-90% of braking is done by the front

larger brake cylinder i suppose you mean caliper, dual piston calipers or just calipers with larger pistons can improve braking response. i know the rear calipers on 318 models have a diameter of about 1.5'' max.

better grade brake fluid does react different to heat basically the system is DOT 3, DOT 4 DOT 5, DOT 5 being the highest grade, but i dont know if it compatible with all cars.

calipers dont really have gaskets, they do have a few seals inside including the dust boot that is visible, but unless you have a leaky caliper they should not need replaced.

not sure about replacing your brakes with M3 brakes, but i'm sure with the braking performance that would incur might be worth any inconvenience.
Good Luck!

maurolin
02-06-2005, 03:57 AM
the componets then help stabilize the car under high speeds and braking are not only shocks and springs, rotors and calipers.

a bad ball joint, or a control arm bushing NOT OFFSETTED like on the 95 M3 will create a "wabbly" feel on the steering and the car will "move" left and right while hard braking.
the control arms play a KEY roll when braking, as most of the weight is now shifted to the front of the car.
a loose steering rack and bad tie rod ends will also contribute to braking vibrations and wabblyness.

1996 328ti
02-06-2005, 05:54 AM
When my LCA bushings were shot the front wheels felt like they were like the wheels on a shoping cart. Under moderate braking the steering wheel shock violently. The bushings werre torn in two places. I since went with solid 95 M3 bushings.

maurolin
02-06-2005, 09:39 AM
I am getting mine replaced today. my wheel is shaking like a sex toy!

gadgetphreak
02-06-2005, 07:00 PM
Also upgrading to vented rotors will help with heat dissipation and reduce brake fade.

Not sure if you can just swap in the vented rotors in place of your solid units... (I would think you could). Someone else here may know whether thats possible or not.

EDIT: (just read this other thread which answers my question):

http://www.318ti.org/forum/showthread.php?t=4403

motorsport
02-06-2005, 11:30 PM
i dont know if your calipers for the solid rotors are compatible with vented, because vented rotors tend to be thicker so i dont know if you could get your caliper/pad assembly to slide on...even fully compressed.

1996 328ti
02-06-2005, 11:58 PM
i dont know if your calipers for the solid rotors are compatible with vented, because vented rotors tend to be thicker so i dont know if you could get your caliper/pad assembly to slide on...even fully compressed.
The calipers are different and vented calipers are cheaper.

maurolin
02-07-2005, 04:40 AM
dually but firmly and strongly applied the brakes (Not slamming but braking as hard as I could) and le the wheel go. (huge emty road) and my car gave me a perfectly straight stop. After my ears popped, I realized that I had brought the car from 90mph to 0 in a matter of a few seconds. so I got out to look at the position of the tires and to take measurements (looking for off toe or camber) and the repair was a success!.
Tomorrow, I will be changing the brake fluis to Super blue racing dot 5 (or is it 4?)
I do tell you... took the mechanic almost 3 hours to get the balljoints out.

RQti
02-13-2005, 05:52 PM
I'm new to the forum so maybe I haven't looked in the right place for the answer.
My girlfriend has a '97 ti and I have had problems replacing the rear brake pads. I work on equipment and my own vehicles all of the time and know what I'm doing but I just cannot get the rear pads in the calipers. I'vew used NAPA pads and then got AXXIS pads and both seem to be too thick for both pads to fit into the caliper at the same time. I am compressing the caliper and have tried many differnt ways to get them in.
The Axxis part # is 088-15620 and the NAPA # is AE-7631M.
Are these the correct pads? Or am I doing something wrong.
Thanks in advance for your help.
RQ

1996 328ti
02-13-2005, 10:31 PM
You compressed the piston all the way in?
I have a set of Ultimate Axxis on there right now.
I don't recall the part number though.

RQti
02-13-2005, 10:36 PM
Yes compressed all the way in where the metal of the pad is touching the caliper housing.

1996 328ti
02-13-2005, 11:50 PM
I remember this problem on the ti mailing list.
Not sure of the brand or the outcome.
My guess is there is a problem with the pads.
Maybe mislabeled by the manufacturer?

motorsport
02-14-2005, 03:52 AM
yea NAPA doesnt know crap about bimmers

RQti
02-14-2005, 03:55 AM
Yea, me neither apparantly!