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E28 M535i brake upgrade. Anyone done this before?

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thats an unfortunate run of events. but having said that once you have the parts (and part nos are supplied in my earlier post) it is a very simple plug and play upgrade which makes the world of difference

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Right, it’s finally sorted and I’ve collated everything. I decided to do a proper job of it and went with the huge (and hugely expensive) stage 8 upgrade listed above in eamos’ post. Here are the details, prices (inc. VAT) and part no’s for the whole carry on (note; part no’s are for standard BMW parts, with the exception of the Goodridge hoses, but they may help companies find the right fitting);

All Round

Goodridge stainless braided brake hose 6-line kit with stainless fittings* and red sleeves* to fit E28 M535i 85-88 (*these cost extra).

Goodridge part no: KCB-283-172-6

Cost: £116 inc. postage from www.munichlegends.co.uk

Discs: EBC vented plain* discs (*i.e. not slotted or cross drilled) to fit E31 with Brembo callipers (size 324x30mm).

Part no: 34 11 6 756 087,

Cost: £260 pair from www.ebcbrakes.biz

Rears

Callipers: Single piston BMW floating callipers to fit E34 540/M5.

Left: 34 21 1 160 399, Right: 34 21 1 160 400, Carrier (2 req’d): 34 21 1 160 384

Cost: £125 for 2x used callipers and carriers from www.balancemotorsport.co.uk

Pads: EBC Yellowstuff pads to fit E34 540/M5.

Cost: £46 for four from www.motormec.co.uk).

Munich Legends in general have been extremely helpful and very knowledgeable on the subject of upgrading old Bimmers. I had heard complaints about bad experiences with the company before, but I called in and found that it’s been under new management, for a little while now, in the form of one Alex Turk. He seems to be doing his absolute best to reform the business, which can only be a good thing.

There are quite a few companies on the web selling EBC brake bits. I went with the cheapest companies for each of the parts and had no problems with the companies I purchased them from. The problems came from UPS losing the rear bits and EBC themselves with supplying the front discs.

The standard front dust shields have a lip which has to be straightened out in order to fit the 8 Series discs (324mm diameter, up from 282mm). I thought they may explode in a cloud of rust when bent out of shape. The backup plan was to fit 8 Series dust shields, which apparently are a straight bolt-on fit. Amazingly, the 23 year old steel hammered flat without disintegrating. I think the standard rear dust shields are fine and don’t interfere at all. The E34 vented rears still have a drum handbrake and take the same size shoes.

I also tracked down the full file eamo got the upgrade list from. It has lots more useful info in it. I’ll post that, if anyone can be bothered to read it after War and Peace here…

The brake master cylinder is still the standard E28 item, though a new one. I’ve found that the pedal feel seems a bit heavier and to have slightly shorter travel, but is much more responsive. How hard I press now makes a difference to how fast I stop. It still feels like standing on a hammer compared to the brake feel in my pals Integra Type-R (also Brembos), but a huge improvement over standard. Eamo’s full file goes into detail about the subject of fitting an E32 7 Series master cylinder. It states that the standard E28 cylinder is fine, even with the huge callipers, and even suggests that the E32 cylinder may make the pedal too ‘sharp’ to effectively modulate the pressure under hard braking. The 7 Series had a bigger cylinder because of the extra weight it has to stop.

This calliper change also moves the brake bias more rearwards, from 73% / 27% front bias to 70.5% / 29.5%. Apparently the best balance for E28 535 is 68% / 32%, which you get with E34 M5 bits all round. I’ll have to try it on the track to see what the difference is.

An issue which has cropped up is unsprung weight. The weight for both standard front callipers, discs and 4 pads is 23.2kg. This goes up to a considerable 30.3kg for the Brembo kit. The E34 M5 bits are 30.9kg while standard E31 8 Series single piston brakes are a whopping 33.3kg. This has impacted the handling. The steering is noticeably heavier than before. Also, it didn’t like bumps or truck ruts before. It gets really unsettled by them now. It’s running on 17” BK Racing 141 wheels (the cheap Alpina look-a-like ones) with 215/45R17 Goodyear Eagle F1 GSD3 tyres (the ones with reinforced sidewalls, purchased after the sidewall of a GSD2 blew out on me). On the bumpy lanes around here I have to keep a good grip of it. When I hit a bump, the car seems to ‘dive’ into it and make a not small course adjustment on its own if I don’t have a hold on the wheel. It isn’t a hazard or even that big a problem really, just something to be aware of. I’m hoping that fitting Whiteline anti-roll bars and poly bushes will go some way to reducing this effect, as mine are still original at present.

If you want part no’s, I highly recommend this: www.www.barryboys.co.uk.co.uk

And finally, a big fat THANK YOU to eamo, jonah, classic-md-autos, splondike, duncan-uk and anyone else who has contributed or been following my ramblings in this incredibly long, drawn out thread. The phrase ‘pulling teeth’ springs to mind when I think about it. Your help and wealth of knowledge are much appreciated.

Conclusion

The total cost of this upgrade was near enough £2000. The parts alone were £1600. That’s an awful lot to spend on stoppers. The question is, was it worth it? Short answer; yes.

The car went for its MoT with the brakes just fitted and promptly failed because they virtually didn’t work. One thirty mile run later and they still didn’t work. My regular wangled it through (after a right old barney with the test centre, apparently) and told me to drive very carefully as they were taking a very long time to bed in. It took over 500 miles of general use to get them working properly. If that isn’t an omen for their hardiness, I don’t know what is. I had a chance to properly test them on the weekend as well, thankfully now that they’re working. An oik in a 106 pulled out on me near Oxford (I really hate driving around there. See an earlier post…). I stamped on the pedal, the nose dipped and the car went from 40-0 in about 4 car lengths. No ABS grinding, no skidding, no weaving, no drama at all, just two pale teenagers with eyes the size of saucers and one relieved M535i driver. With the standard brakes, I think there would have been another trashed 106 and another hefty repair bill from my regular independent (I have no doubt whatsoever that the damage to the big blue brick would have been superficial, but costly).

Finally, why upgrade? The E28 M535i brakes were slated when it was new in 1984. In all the period reviews I’ve read, the brakes are the only area this car didn’t shine. By modern standards they’re fairly poor. I’ve had a couple of scares on the road over the years and mine were always in good order and I don’t tailgate or drive like my pants are on fire 99% of the time. After I annihilated them at Castle Combe, I wanted some damn good replacements. At the National BMW Festival in August, I was asking about the Brembo upgrade. One fellow (sorry, can’t remember his name) asked me “Do you really need that much brakes”? My answer at the time was “Probably not, but that’s what I’m looking at”. Now I can say that I definitely don’t need this much brakes for road use, but I definitely want this much brakes! For road use only, I think that E34 540/M5 setup all round and EBC Greenstuff pads would be more than enough (note; I was warned off EBC Redstuff pads as, while even better than Yellowstuff, they’re very abrasive and eat discs with track use!). The Yellowstuff pads scrape as the car turns and they squeal like mad if you only brake lightly, but I don’t care. Even though I haven’t had the chance to track them and get them up to full temperature yet, I’m dead chuffed with the way they’ve turned out and would recommend this upgrade to anyone wanting some very serious brakes. If you can afford it, mind!

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What are the bolt on BMW upgrade?

Many people have started upgrading the brakes on their E28s. Well here is a list of BMW brakes and the cars they come off of, which fit the E28.

Notes to keep in mind:

1. You may need larger wheels and tires if you increase the size of your brakes.

2. Remember that the pads are different then the stock E28 brakes.

3. Prices are list prices in Euros (accurate as of Fall 2003). US list (dealer) prices must usually add between 25% and 40% mark-up, depending on currency exchange, market, and dealer mark-up.

Front Brakes:

E32 (all US models, 735, 740, 750)

The calipers are single piston. To be used with 302mm diameter x 28mm thick rotors.

Caliper part #: 34 11 1 160 363/364 (199.50 Eur)

Rotor Part #: 34 11 1 159 896 (superceded by 34 11 6 756 090) (72.30 Eur)

Carrier Part #: 34 11 1 160 365 (91.80 Eur)

Note: E36 US M3 pads can fit this application.

E28 M5/ E24 M6 (US and Euro)

The calipers are 4 piston. To be used with 300mm diameter x 30mm thick rotors. E32 302mm diameter x 28mm thick rotors can be substituted.

Caliper Part #: 34 11 2 225 002/003 (432.60 Eur)

Rotor Part #: 34 11 2 225 007 (102.60 Eur)

Substitute Rotor Part #: 34 11 1 159 896 (superceded by 34 11 6 756 090) (72.30 Eur)

No carrier.

E34 (all US models, 525i/535i/530i)

The calipers are single piston. To be used with 302mm diameter x 22mm ventilated thick rotor.

Caliper Part #: 34 11 1 160 367/368 (194.00 Eur)

Rotor Part #: 34 11 1 160 936 (75.50 Eur)

Carrier Part #: 34 11 1 160 366 (91.80 Eur)

E34 (540i, US model)

The calipers are single piston, floating. To be used with 302mm diameter x 28mm thick rotors.

Caliper part #: 34 11 1 160 363/364 (199.50 Eur)

Rotor Part #: 34 11 1 159 896 (superceded by 34 11 6 756 090) (72.30 Eur)

Carrier Part #: 34 11 1 160 365 (91.80 Eur)

E34 M5 3.6 (US model), E34 540i Sport (US model)

The calipers are single piston. To be used with 315mm diameter x 28mm thick rotors.

Caliper Part #: 34 11 2 226 407/408 (also 34 11 2 226 873/874) ( 281.00 Eur)

Rotors Part #: 34 11 2 226 385 (100.50 Eur)

Carrier Part #: 34 11 2 226 875 (136.50 Eur)

E34 M5 Euro Nurburgring brakes

The calipers are 4 piston calipers, to be used with 345mm diameter x 32mm thick directionally ventilated rotors.

Caliper Part #: 34 11 2 227 115/116 (555 Eur)

Rotor Part #: 34 11 2 227 735/736 (198 Eur)

No carrier. [Note these brakes were available on EURO 850CSi.]

E31 (US model, up to 8/93)

The calipers are single piston. To be used with 324mm x 30mm thick rotors

Caliper Part #: 34 11 1 160 325/326 (215.00 Eur)

Rotor Part #: 34 11 1 159 895 (77.50 Eur) [Note]

Carrier Part #: 34 11 1 160 327 (94.50 Eur)

E31 (US model, after 8/93)

The calipers are four piston, known as “Brembo” brakes. To be used with 324mm x 30mm thick rotors.

Caliper Part #: 34 11 1 161 177/178 (289.00 Eur)

Rotors Part #: 34 11 1 161 086 (superceded by 34 11 6 756 087) (100.50 Eur)

[uS 850CSi Rotor Part #: 34 11 6 757 746 (75.50 Eur) (same used on E32 750i Euro, and E38 and E39 V8 engine cars). Note: US 850CSi rotor Part #746 is used with calipers #325/326. Note: Although #746 is the same rotor used on E38s and E39s, the carrier's bolt spacing to the struts on E39s/E38s are not the same as E24/E28/E31/E32/E34.]

No carrier.

Rear Brakes:

E34 non-vented (US model 535i/530i/525i)

The calipers are single piston. To be used with 300mm x 10mm thick solid rotors

Caliper Part #: 34 21 1 157 557/558 (superceded by 34 21 1 160 381/382) (135.50 Eur)

Rotors Part #: 34 21 1 162 305 (superceded by 34 21 1 160 305) (49.00 Eur)

Carrier Part #: 34 21 1 160 383 (83.10 Eur)

E34 vented (US model 540i/M5/540i Sport)

The calipers are single piston. To be used with 300mm diameter x 20mm thick vented rotors

Caliper Part #: 34 21 1 159 657/658 (superceded by 34 21 1 160 399/400) (155.00 Eur)

Rotor Part #: 34 21 1 165 265 (70.80 Eur)

Carrier Part #: 34 21 1 160 384 (83.10 Eur)

E32 non-vented (US model 735)

The calipers are single piston. To be used with 300mm diameter x 12mm thick solid rotors. E34 solid rotors are required. Carrier information as to which is acceptable is unavailable at this time.

Caliper Part #: 34 21 1 160 353/354 (152.00 Eur)

Rotor Part #: 34 21 1 165 257 (60.50 Eur)

Carrier Part #: 34 21 1 160 355 (83.10 Eur)

E32 vented (US model 740i/750iL)

The calipers are single piston. To be used with 300mm x 20mm thick vented rotors (E34 vented rotors must be used!)

Caliper Part #: 34 21 1 160 399/400 (155.00 Eur)

Rotor Part #: 34 21 1 165 265 (540i) (70.80 Eur)

Rotors that came on E32 Part #: 34 21 1 162 967 (will not fit E28/E24 application. Reference use only.) (69.80 Eur)

Carrier Part #: 34 21 1 160 384 (83.10 Eur)

E34 Nurburgring (M5 Euro)

To be sued with 328mm diameter x 20mm thick vented rotors.

Caliper Part #: 34 11 2 227 873/874 (191.00 Eur)

Rotor Part #: 34 11 2 227 844 (93.40 Eur)

Carrier Part #: 34 11 2 227 875 (127.00 Eur)

Here are an example list of stages of braking upgrades and the minimum wheel size you can safely fit. The amount of benefit you receive from the upgrade is mainly dependant on the pads and rotors you use.

Stage 1: E32/540i fronts

Minimum wheel size: 15” wheels

Stage 2: E28 M5/ E24 M6 fronts

Minimum wheel size: TRX, only *some* 15” wheels, 16” wheels

Stage 3: E32/540i fronts, E34 solid rears

Minimum wheel size: 15” wheels front and rear

Stage 4: E28 M5/ E24 M6 fronts, E34 solid rears

Minimum wheel size: TRX, only *some* 15”, 16” wheels front; 15” wheels rear

Stage 5: E32/540i fronts, E34/E32 vented rears

Minimum wheel size: 15” wheels front and rear

Stage 6: E28 M5/ E24 M6 fronts, E34/E32 vented rears

Minimum wheel size: TRX, only *some* 15”, 16” wheels front; 15” wheels rear

Stage 7: E34 US M5/US 540i Sport front and rear

Minimum wheel size: some 16” wheels front; 15” wheels rear

Stage 8: E31 front, E34/E32 vented rears

Minimum wheel size: some 16” wheels front; 15” wheels rear

Stage 9: E34 Euro, E31 850CSi Euro (Nurburgring brakes)

Minimum wheel size: 17” wheels front; 16” wheels rear

We recommend against slotted or cross-drilled rotors for use in daily driving application, and most other applications. In our experience slotted rotors give a different and strange vibration feeling through the pedal. This can be disconcerting in normal street use and even worse on track. We have also found that slotted rotors have a tendancy to wear out pads very quickly. Cross-drilled rotors are generally more susceptible to cracking, and also increase vibration. Good quality normal rotors are best for almost all applications, including track use (for example, Balo rotors).

Good, dustless or low-dust street pads are recommended as the following (these are just a few examples, there are many other manufacturers of brake pads that offer good products).

1. PBR Deluxe and Metalmasters – good original equipment replacement. Best for daily use, in a variety of ambient temperatures.

2. Mintex, Pagid – slightly more aggressive pads. Good daily use, with some aggressive use. Better in warmer temperatures.

3. Porterfield R4S – aggressive pads that can be used on the street. These are better suited for hard street, auto-x, and Driver's School use. They work well under higher temperatures so cold stopping will be reduced.

4. Porterfield R4, R4E, Hawk – track pads. Recommended not for use on the street.

Best Value recommendations:

1. E32/540i Front brakes (Stage 1)

2. E32/540i Front brake; E34 solid or E32/E34 vented rear brakes (Stage 3 or 5)

Best Performance Recommendation:

1. E32/540i Front brakes; E32/E34 vented rear brakes (Stage 5)

2. E28/E24 M5/M6 front brakes; E32/E34 vented rear brakes (Stage 6)

3. E34 M5/540i Sport (Stage 7)

Ultimate Performance:

1. E34/E32/E31 Nurburgring Brakes

2. Custom brakes (Mov’it, Wilwood, Brembo, etc. Not addressed here.)

Written by Rob Anderson '01 (updated Chris Graff ’03)

Additional Brake Upgrade Information

Richard Nott’s Database Information Corrections:

Below in italics are quotes from Richard Nott's Database (

The E32 rotors are vented internally, which allows better cooling in most everyday driving situations. However, M5 brake rotors are externally ventilated. With the correct choice in wheels (as evidenced with the E34 M5), that combination is more effective at brake cooling (without custom brake ducts)

The biggest reason to for E32 brakes is best economic value (initial cost and consumable costs).

The 540i/6 fronts may be considerably cheaper the E34 M5 and are the same size. The stock E28 ///M car brake bias is calculated at 73% front and 27% rear. The upgrade to E34, M5 rear brake will change the bias to 66% front and 34% rear.

The 540i/6 fronts are not the same size as the E34 M5. They are only 300mm. However, they are thicker rotors than the normal E34’s (like the E32’s). Check the part numbers.

the E28 M5 used the same rear rotors as the 535i. Which should tell you how important rear brakes are in the big scheme of things. An increase in pedal firmness can be gained by installing the master cylinder from the E-32, 750 that has a 25mm cylinder bore.

Brake bias is extraordinarily important for correct balancing of the car. The reason the E28 M5 had such an “off” brake balance is due to its weight distribution (roughly 54% front, 46% rear). Similarly the stock 535i had pretty “poor” brake bias. Increasing the front brake bias means that the front brakes are more likely to lock up before the rears, thus giving a nice cushion of safety (understeer) with ABS. More rear bias will generally tend to make a car more responsive in handling and turn-in better (while braking). The E34 brake bias was further rear due to it’s near 50/50 weight balance, and the requirement for correct bias for its weight balance.

The brake bias table is listed below (calculated from brake torques):

Stock E28 535i: 72.8% / 27.2%

E28 M5 front set-up: 73.8% / 26.2%

E28 M5 with E34 rear (vented or non): 64.3 % / 35.7%

E32 7-series front alone: 76% / 24%

E32 fronts with E34 rears: 66.9% / 33.1%

E34 M5 front with E34 rears: 68.2 % / 31.8%

E31 fronts Brembo with E34 rears: 70.5% / 29.5%

The ideal brake balance for high performance driving [with a roughly 52/48 weight distributed E28 535i] is actually the E34 M5 fronts with the E34 vented rear brakes. The E28 M5 front calipers with E34 vented rears moves the bias more rearward, and thus can be more beneficial in on-track situations for handling (turn-in). Similarly, all other things being equal, E28 M5 calipers give better feel than the E32 front calipers due to their multi-piston, fixed caliper design, which increases stiffness over the floating caliper design.

To make an E34 535 out brake 540's, be on par with E34 M5's and have the same brake reaction times as the M3 Lightweights, The E34 rotors can be gas slotted, but needs to be done by an experienced race shop. You then add super blue fluid, and install a street/track carbon-kevlar pad set, (or similar) but this is only suited to the track, as the pads take time to warm up. On the street the pads will wear out 15% quicker. Personally I would change the pads to Deluxe or Metal Master. Metal Masters handle harder driving, but don't stop as well cold as the Deluxe. Deluxe don't dust, are good when cold and don't chew out the rotors like Metal Masters.

1. PBR Deluxe and MM pads are great for solely street use.

2. Super blue fluid is not necessarily recommended as it tends to stain. If you really want to use the ATE fluid, use the gold colored one.

3. Track/race pads do NOT wear out 15% quicker than street pads. Each pad’s wear rate depends on a number of factors. One cannot give such a blatantly overarching statement that they wear 15% quicker. I’ve seen Porterfield R4S wear out in 15k miles, and PBR Metal Masters wear out in 50k miles. It really depends on temperatures, use, pad compound, and driving style.

Recently, I went to E34 M5 fronts (same caliper, 315mm rotor). For the track, this setup is great, but probably not worth the extra money on the street, as the M5 brakes are very hard to find.

As I mentioned below, the E32 750il master cylinder is also highly recommended.

-------------------------

The 540i calipers, carriers and rotors - both front and rear - are a bolt-on for the E28/E24.

In addition, the E34 M5 calipers, carriers and rotors - both front and rear - are a bolt-on for the E28/E24.

The only differences between the two are the front carriers and rotors. The M5 carriers must be used with M5 rotors, to accommodate the larger diameter.

-------------------------

While it's true the 540i/740i/750i front brake calipers are the same, the caliper bracket and rotor are different. The bottom line is, you'll need to get a complete M5 kit, since the brackets are very difficult and expensive to get separately.

....

2) I believe that 540i/6 fronts are the same 315mm x 30mm as the E34 M5, and may be considerably cheaper

Again, this is false. The 540i/6 fronts are not the same as the E34 M5 fronts. They are the 302mm diameter E32 type. You can check this with any parts list or parts catalogs.

However, the M540i/540i Motorsport limited edition model came with the E34 M5 3.6 front brakes (the 315mm diameter ones). That limited edition model also came with a host of other M5 components (for example, sport seats, front spoiler, and the electronic damping control).

Note on going with TOO big brakes: Unsprung Weight and inertia

There is one important aspect to consider when looking at upgrading brakes - your brakes are unsprung weight. Unsprung weight is an important aspect to suspension tuning, and excessive unsprung weight can be a problem as it detrimentally affects handling and damping.

So, for comparison purposes, below are the total (left and right) unsprung weights of different front brake packages. (All weights are referenced from the ETK).

E28 stock front brakes, floating caliper

Pad set: 1.806 kg

Caliper & carrier: 4.57 kg ea

Disk: 6.148 kg ea

Total (L&R): 23.2 kg

E32 7-series front brakes, floating caliper

Pad set: 1.986 kg

Caliper & carrier: 5.2 kg ea

Disk: 8.08 kg ea

Total (L&R): 28.6 kg

E28 M5 / E24 M6 front brakes, 4-piston

Pad set: 1.5 kg

Caliper: 5.0 kg ea

Disk: 8.64 kg ea

Total (L&R): 28.7 kg

E34 M5 3.6 front brake, floating.

Pad set: 1.896 kg

Caliper: 5.14 kg ea

Disk: 9.36 kg ea

Total (L&R): 30.9 kg

E31 Brembo, 4 piston

Pad set: 2.005 kg

Caliper: 3.4 kg ea

Disk: 9.74 kg ea

Total (L&R): 30.3 kg

E31 front brakes, floating caliper

Pad set: 2.047 kg

Caliper: 5.87 kg ea

Disk: 9.74 kg ea

Total (L&R): 33.3 kg

Written by Chris Graff '05

Rebuilding Brake Calipers

As our car age, various things go wrong that you would not expect to have happen on a new car. Some of these problems most DIYers don't think twice about attempting, but there are some things that most people shy away from. For example, the average DIYer will have no problem doing a brake job, but when they find out that they have a stuck caliper, many just think that their only option is to purchase a remanufactured unit through a dealer or Maxamillian. Well, this is not the case, BMW and Maxamillian sell what are known as caliper rebuild kits. These kits come with all of the necessary rubber O-rings to rebuild a caliper. Now lets say you have a stuck caliper on your M535i, and you have decided that you want to attempt to rebuild your own caliper(Which is not something I suggest to an inexperieced DIYer).

First, you need to remove the outer dust boot. Once this is removed you must remove the piston out of the caliper. To do this you can use one of three ways. The first one is to just push on the brake pedal until it pops out. This is accomplished by having the rest of the brakes on the car and working correctly, then you unbolt the questionable caliper from the trailing arm or strut tube and then you remove the pads. Once this has been done, then you have a friend push on the brakes. You will see the piston start to move. Now you will want to have a catch can under the caliper because as soon as you get the piston out the brake fluid that was in the reservoir and in the brake line will come out. Be careful to catch the piston when it pops out because you don't want to damage it. This is an easy way of removing the piston, but you will find that you can only do one caliper at a time and then you have to bleed the system before you can do a second one. It is also difficult to rebuild the caliper with it still attached to the brake line. So the second and third way involve removing the caliper completely from the car, this is also the preferred way to rebuild a multi-piston caliper like those lovely E28 M5 calipers that you just bought to put on your car. The second way to remove the pistons is to used compressed air. In the port that the brake line screws into, you pump compressed air into the caliper and this will push out the piston. This is the preferred way to do this step. Now, some of us who have rebuilt quite a few calipers have found that the fluid, and the compressed air won't loosen the piston. Well don't worry, there is one more way of removing the piston. This involves using a vise grip and a vise. First you clamp the vise grip to the piston with as much force as you can. Now remember, you only want to clamp it to the unmachined surface. This is the area that is in direct contact with the pad. You will notice that it has a small diameter then the rest of the piston. Once you clamp the vise grip on, then you place the handle of the vise grip into the vise and tighten it down. Now you need to grab the caliper with both hands and try to rotate the piston in the bore. This is made easier by plenty of releasing fluid. Once you have gotten it to rotate in the bore then you need to carefully pull the piston out of the caliper by pulling and rotating at the same time. The reason why you do both at the same time is because you want to make sure that you don't cock the piston in the bore. If you cock the piston you will find that you can damage the caliper bore. Now, people with the M5 multi-piston calipers will be asking, how do I get the vise grip on the piston. Well what you need to do is unbolt the two halves of the caliper. There are four bolts that hold the caliper together. Once you have removed these four bolts put them in a safe place because they are no longer available from BMW. You will also notice that there are two spacers, and four small O-rings. Non of these parts are available from BMW anymore, so it is important not to lose them. I suggest that once you have the small O-rings out that you soak them in NEW brake fluid. WHEN REBUILDING CALIPERS ONLY USE NEW BRAKE FLUID!

Now that you have the piston out, you open your rebuild kit. There is a larger rubber O-ring in the kit. This O-ring is actually placed in a groove in the caliper bore. You need to remove the old O-ring. Then it is time to clean out the caliper. This is easily done with compressed air, but can also be accomplished by plenty of brake parts cleaner. Once you have cleaned out the caliper you need to inspect the bores. If you see any rust in the bore, you will need to clean it out. This is done by carefully and I mean carefully using some emery cloth on the rust spot. Now that you have gotten rid of the rust spot, you need to inspect the bore for any scoring. If there is some slight scoring you can probably smooth it out with the emery cloth, if there is deep scoring you will need a new caliper. Once you have cleaned and inspected the bore you will need to coat it thoroughly with brake fluid. Then soak the new rubber O-ring in brake fluid and install. Make sure that the seal is not twisted in any way. Now you need to clean any rust off the piston and also inspect it for scoring marks. Once you have cleaned it and inspect it, you can cover it in brake fluid and carefully reinstall it in the bore. You must be very careful doing this because you need to make sure that you don't cock the piston. But unlike removing the piston you cannot rotate and install the piston at the same time. You need to push the piston in by hand. You will know if the piston is cocked because it will become very very difficult to install. Now remember you will need to get the piston by the rubber O-ring so don't mistake getting the piston by the O-ring with it being cocked. Now that you have the piston back in you need to put on the new dust boot. Once you have that on, the piston caliper is back together. And for those with the M5 calipers, you will need to bolt back together the two halves of the caliper. Make sure to clean everything and wet it down with break fluid. Also make sure you reinstall all of the small rubber O-rings and make sure not to pinch them. Once everything is back together, I suggest for your floating caliper to use high temp. wheel bearing grease on the guide bolts. This will ensure smooth operation of the caliper. Bolt the caliper back onto the car and bleed the brakes.

Now you have successfully rebuilt your caliper and probably saved yourself at least $100 for each caliper.

*The E28 M5 caliper is just like any other multi-piston BMW caliper and so the techniques can be applied to all multi-piston BMW caliper.

Written by Rob Anderson '01

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Well I take my hat off to you, thats one hell of alot of writing and very well written too!! very easy to read. Unfortionately you had to spend £828 on brembos before you even started, where as I paid £105 for my two, and now just £50 to rebuild them, as I was shocked by the total overhall bill, but you cant really put a price on good brakes. Any pictures of the upgrades?? How did you do the thirty miles of driving, did you do it with no M.O.T?? Very interesting about the master cylinder and the weight of the 7 series... alot of divided opinion about the master cylinder and bigger calipers/pistons. Great article will be reffering to this when i do my 840/540i to my E34 great stuff keep it up!!

Jonesy

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Thanks Jonesy. Everywhere I contacted (and I tried just about everywhere) and asked about 8 Series Brembos, the answer was "Ha! Good luck!". I think you've done very well there, make the most of it.

Erm...I'm not too good at the internet. I've read the guide to posting pictures, but I haven't got around to trying to make it work yet. As I said, I intended to do the work myself (and photo it in stages) but had to have it done for me due to non-BMW related commitments (i.e. work and family events). I might try taking some wheels off and snapping some pics in the future.

Aaah...thirty miles with no MoT...erm...it happened to be thirty miles to the test centre? Yes, thats it... :)

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I've just realised that there's a link for EBC Brakes Direct on the Board Index offering 15% off for BMW5 forum members. Just enter the code listed for a discount. Was that there when I ordered mine 3 months ago? If it was, D'OH!

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Has anyone else fitted Goodridge hoses and had a problem getting a seal?
I'm replacing all the hard lines on my car and all the flexis with Goodridge lines. I do hope this isn't going to be an issue, I will be most upset!

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Hi, watching this thread with interest, with my blue E28 in mind, have just this morning test fitted 345mm four pot fronts with alloy bell discs from a late E34 M5, and the 328mm vented single pot rears to go with them. All a direct fit! Need to be careful wih the wheels though, an early E34 M5/ 850 wheel fits, the 8 x 17 Remotecs the car currently runs wont even go over the rear brake! :shock: I'm looking to use the 328mm rears and a bespoke setup on the front, with a 360mm ish disc, with carefully chosen 18" wheels. The fronts (before you ask!) are off to Malaysia along with a set of 300mm vented rears for an E28 528i racer being put together by a very good friend.

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Ye Gods! Are you looking to stand this thing on its nose?

Are you intending this for track use, road use, or both? Have you run large brakes before (I'm going to guess that you have) and, if so, what anti-roll bars does yours have? The extra weight, combined with the 215x45xR17" wheels and tyres, has upset the handling on mine. I'm looking at fitting Whiteline anti-roll bars and poly bushes to (hopefully) negate some of the 'waywardness' the front now has on bumpy roads and in truck ruts. I'm also considering 16" wheels, which should just fit. Any experience you could share on this subject would be appreciated.

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The extra weight, combined with the 215x45xR17" wheels and tyres, has upset the handling on mine. I'm looking at fitting Whiteline anti-roll bars and poly bushes to (hopefully) negate some of the 'waywardness' the front now has on bumpy roads and in truck ruts. I'm also considering 16" wheels, which should just fit.

by waywardness i assume you mean tramlining - 17's will exacerbate this and 16's will improve matters a bit, i assume all the suspension arms and linkages are in good shape? ie recently replaced.

These cars will never be pin sharp with the steering box but a little wear in every component adds up.

certainly look at TCA bushes, centre link, steering box play and the steering box mount.

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Hi Duncan. All bushes, arms, sway bars, etc. are less than 2 years old and in good order. In fact, just about all of the suspension on the front end has been replaced in the last 4 years, includimng the struts. I need to check the steering box, I haven't for a while but it was good on the last check. 'Waywardness' means tramlining and responding badly to bumps, potholes, rippled tarmac, speed cushions, large camber changes, in fact anything that puts an uneven force on the front wheels. It was there before the brake mod, I put it down to the large and not too light wheels (bk racing 141 'Alpina' look-a-likes), but it's fairly pronounced since the big brakes. It's not a massive problem, mostly just an annoyance, but the roads around here are dismal and I want to eliminate it as much as possible. I'm considering paying for some modern (eek!) light wheels as well as 16s to reduce the unsprung mass. I'm told OZ Racing do some very lightweight alloys in 17". I imagine you'll pay for them mind, and I haven't found out if they'll fit an E28.

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Hi Duncan. All bushes, arms, sway bars, etc. are less than 2 years old and in good order. In fact, just about all of the suspension on the front end has been replaced in the last 4 years, includimng the struts. I need to check the steering box, I haven't for a while but it was good on the last check. 'Waywardness' means tramlining and responding badly to bumps, potholes, rippled tarmac, speed cushions, large camber changes, in fact anything that puts an uneven force on the front wheels. It was there before the brake mod, I put it down to the large and not too light wheels (bk racing 141 'Alpina' look-a-likes), but it's fairly pronounced since the big brakes. It's not a massive problem, mostly just an annoyance, but the roads around here are dismal and I want to eliminate it as much as possible. I'm considering paying for some modern (eek!) light wheels as well as 16s to reduce the unsprung mass. I'm told OZ Racing do some very lightweight alloys in 17". I imagine you'll pay for them mind, and I haven't found out if they'll fit an E28.

i have a similar problem with the 17" style 5's i have. like you every single suspension and steering component was replaced with oem stuff in the last 6 months.

i now run 16" BBS RS005 on front and 006 on rear and this helps a great deal. not totally eliminated but a huge difference. the next thing i will do which should cure it will be to relocate the battery into the boot

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i think its wheel size and width rather than weight - how do you imagine relacting the battery will help?

I may (not yet decided) have a M5 battery box and carpet set for sale....

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Assuming were discussing 535s here, I think I can answer that. Good batteries (I use Bosch Silver) are very heavy, and in the regular E28s sit in the very front left of the engine bay. M30 engined E28s are, I think, 53/47% front biased weight distribution. The E28 M5 had components re-distributed during design to balance this slight nose heavy bias, resulting 51/49% front (I think, again). In theory, moving as much as possible to the boot would help handling.

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appreciate the weight bias issue and its effect on handling but i don't see how this would remove the inherent numbness and tendency to tram line that an e28 on big wheels exhibits.

It might reduce under steer a touch but thats it i would think?

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Duncan

With me my problem lies more so with taking corners at high speed. its fine on a straight or bumpy road. but when i push the car on into corners i find that you instinctively turn the steering wheel a certain amount and then realise going thought the corner you need to turn it a bit more, then turn back again. its hard to explain but if you drove it you would understand

replaing the 17s with the 16s has seriously reduced this sensation by a huge amount. i compared the weight of the style 5 with the rs005 and there is a big difference!! couple with the extra wieght of the bigger calipers and disks all adds up.

so by sticking the battey in the boot as well will go a long way towards cancelling out the extra unsprung weight added by the bigger disks and calipers

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i fear its just the box set up (by design) rather than weight. mine is numb at the helm and its not accurate like a decent R&P set up.

Its just the way it is - 16's help and the weight shift can do no harm but it done' think it will erradicate what you feel.

what you describe is the reason i have a slice of e28 in the garage with the steering box, linkages, x-member and struts with a view to mocking up an R&P set up.

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what you describe is the reason i have a slice of e28 in the garage with the steering box, linkages, x-member and struts with a view to mocking up an R&P set up.

If you get around to it, please let us know how that goes. I'd love to drive an E28 that doesn't have to be muscled around bends at speed.

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Hi, sorry for slow reply, virus+too much to do+ not enough hours in a day+ not sleeping properly!!!!!

Firstly, stop beating up the steering box installation, theres nothing wrong with it!

You need to separate all the problems out from each other; tramlining is an inevitable consequence of large rims and wide tyres with low profiles, only minimised by a full geometry check to reset everything to allow for a new ride height if lowering is also an issue, more castor will help if it can be done without making the car too heavy to park. Big brakes will dramatically raise the unsprung weight, therefore as a consequence of the installation, compression and rebound rates on the shock absorbers will all be wrong. moving sprung weight around the car will not change that fact. Having said that, on the subject of batteries, i converted my E28 to a Powervamp aircraft battery in 2006, best thing I ever did. Much better than a bucket of acid.

Anti roll bars are very powerful springs, and although basically inert on a perfect surface in a straight line, and theoretically inert in a straight line over a speed bump, if driven across a bumpy surface an upgraded anti roll bar will make the car fidgety as it rapidly adds and removes spring rate to each side of the car, quite apart from the risks of going too thick giving the car a dry only set-up. Have just fitted M5 25mm/18mm anti roll bars to mine, untested as yet. i'm guessing any thicker on the rear one and i would need to disconnect it in the wet. :)

Cheers

Peter

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Assuming were discussing 535s here, I think I can answer that. Good batteries (I use Bosch Silver) are very heavy, and in the regular E28s sit in the very front left of the engine bay. M30 engined E28s are, I think, 53/47% front biased weight distribution. The E28 M5 had components re-distributed during design to balance this slight nose heavy bias, resulting 51/49% front (I think, again). In theory, moving as much as possible to the boot would help handling.

:lol: Sorry for the late response, I have only just caught up with this, but I have to laugh at this "Claim from BMW back in the day" God it makes me laugh, why weren't they just honest enough to admit that the only reason that the battery ended up in the boot is that there simply wasn't any room under the bonnet for it anymore, they used the battery space for the air box, and it's a bad place for that too, the intake is pointing at the old battery tray, so little opportunity for a good supply of fresh air! Weight distribution IMO had absolutely nothing to do with it.

Basically the cars are old in their design and a handful in what ever guise you have, that's part of the attraction for me. :P

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You may laugh at BMW's reasoning, but the fact is anyone who wishes to improve the handling of an E28 has to accept that weight needs to be taken off the front. At the cost of a rather vulnerable front end, the E12 M535 lost the lower valance, the bumper, runner strip and irons, to hang a bendy plastic spoiler straight off the grille support.

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You may laugh at BMW's reasoning, but the fact is anyone who wishes to improve the handling of an E28 has to accept that weight needs to be taken off the front. At the cost of a rather vulnerable front end, the E12 M535 lost the lower valance, the bumper, runner strip and irons, to hang a bendy plastic spoiler straight off the grille support.

If you look under the bonnet of an E28 M5, you will see that the battery has to go in the boot as there was no room anywhere else, the idea was not exactly new, the humble Mini? If you really want to improve the way an e28 handles, you would do better to make changes to the suspension set up, I am not convinced that the battery out weighs the ABS unit in the o/s front corner. The weight you are going to add with a big break set up will only make things worse. If it understeers (i.e. turn in and it tries to go straight on) then softer springs are needed at the front to give more grip, or at least softer by comparison to the rear, if it's oversteering (i.e. tail happy) then softer at the rear. Obviously anti roll bars will play a part in weight transfere characteristics and decent shock absorbers will control the springs travel. Lowering an E28 will only help upto a point as this introduces negative camber, and so lessening the contact patch of the tyre and reducing grip.

IMO there is only so much you can do, the e28 is tall and narrow. I have managed to do quite a bit with my M5 using custom made springs and adjustable camber plates, it is great on track but not nice on bumpy road services. I strongly believe that there is no real compromise, it is track or road. There are lots of previous threads to be found on here with reference to suspension.

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