E30 5 stud e36 brake conversion ? (220 views) 

Message: there are 3 options for the rear axle:

1. instal the 2 swingarms from a 325i E30, and replace the 4-bolt flanges with 5-bolt flanges from the E36 323ti compact, it fits. take the brake disc from a E36 323ti compact and machine the outside diameter of the disc smaller to the size of a 325i E30 brake disc. then you have 5-bolt with the same brake as a E30 325i

2. instal the 2 complete swingarms and driveshafts from an E36 323ti compact or Z3. it fits the E30 perfect. then you have 5-bolt with bigger brakes than the E30 325i.

3. install the complete rear axle from the Z3 M-coupe. then you have the biggest rear brakes that bmw makes.

option 3 is very expensive because there are almost no used Z3 M-coupe parts for sale.option 2 will cost about 400 to 550 euros.option 1 will cost about 300 euros.

i think option 1 is the easiest for you, because E30 325i swingarms are easily available everywhere, and the 5-bolt flanges and the brake discs are for sale at every BMW dealer

For the front, I have such a recommendation, though 17" wheels are minimum then...

front shocks take E36 M3 3.2 GTtopmounts for the front shocks take E36 325ifront swingarms take E36 M3 3.2 GTfront swingarmbushings take E30 M3 Group N excentricfront hubs, brake calipers and brake discs take E36 M3 3.2 GT

size of the brake discs is 315mm x 28mm, these discs have a centre made out of aluminum.

quite costly, but best performance also for this money...

In detail: 5x120 rear, using MZ3 rear trailing arms.

First, and most importantly the parts list.

Complete trailing arms, left and right.Brake rotors (same as e36 M3 rear)Brake calipersMZ3 halfshafts (much larger/beefier then the e30 unit)MZ3 diff output flanges (much larger bolt pattern then e30 units)

Complete trailing arms

MZ3 trailing arms are far superior to the e30 unit. The overall design is the same but they have added camber/tow bracing that makes them a much more solid design. A complete trailing arm should come with the arm itself, and the hub/wheel bearing still pressed in. Buying bare arms without the hub/bearing sucks. Alot of work for someone without the special tools to press them in.

You will have to use the e30 trailing arm brake hardline. The locating tab on the brake backing plate is missing on the MZ3 backing plate. I choose to cut it off a set of e30 backing plates and tack weld it onto the MZ3 backing plate.

While you have the arms off the car it would be smart to weld on the sway bar re-enforcement tabs. Turner, IE, etc sell them, or you can make them yourself.

Brake rotors

Brakes are a big upgrade with this conversion. The MZ3 rear disc brakes are 312x20mm vented units. The same rotor used by the e36 M3 in the rear. A e30 325i has puny 258x10mm solid rear discs! I'd suggest buying new, but the used ones I got from a 16k mi MZ3 were in very good shape.

Brake calipers

Calipers are standard issue single pistons, much the same as the stock e30 rear caliper in design. They are however much larger! I decided to disassemble, beam blast, paint, and rebuild mine. Rebuild kits are cheap, and not very difficult to do. Rebuilt units can be had for < $100. Got a pair from a 16k mi MZ3, but rebuilt them anyways.

M-Roadster / Coupe rear halfshafts

AFAIK these are unique to these cars. They are much larger in diameter then the e30 units. These list for ~$350 each new, and I had no luck finding rebuilt unit. Got good

used ones from a 16k mi MZ3.

M-Rodster / Coupe diff output flanges

I think these are also unique to these cars, E28 output flanges can be used as well. That may be true but the E28 halfshafts are not! Different design. Get these used. The MZ3/E28 flanges will swap into a e30 diff. They just pull and push in.

The rear suspension swap is pretty straight forward. Unbolt and remove everything related to the stock suspension and remove it. MZ3 arms bolt directly in with no modification. You CAN reuse your stock brake line if your car originally had ABS and rear disc's. It just needs to be bent up slightly to run down the arm and up to the caliper (rather then around the backside etc) Be very careful not to kink the line while you are bending it.

As for the ABS sensor. You have 2 choices. Splice the e30 connector onto the MZ3 sensor, or install the e30 sensor with a spacer. Problem is the e30 sensor is much longer then the MZ3 and would bind on the pulse ring. To solve this problem I found a copper crush ring in the crush ring assortment that was the exact right internal diameter to fit snuggly on the sensor. I think it took 4 or maybe 5 of the crush rings stacked to make up the difference in the length. I installed them with a longer allen screw and my ABS works perfectly. I will double check the # of spacers and photograph it when I get a chance.

The e30 ebrake cable will route through the back of the MZ3 trailing arm and connect to its native ebrake hardware perfectly. The MZ3 ebrake hardware is very similar to the e30, but much larger and beefier. Let me tell you.. I had brand new ebrake shoes on my e30 suspension, and I could drive with it locked without a problem. The MZ3 shoes LOCK the rear wheels. If you try to go anywhere you are out of luck.__________________Jordan SaretteMy e30's Modifications

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Technical_   Chassis_  E30 M3 5-Lug Conversion

E30 M3 5-lug ConversionFred Kim

I.   Parts List/Price Guide

After my friend Dave Adams' 92 330iC was rear-ended, he bought an E30 M3 and swapped his cabrio 5-lug parts onto the M3. I took that opportunity to buy the M3 5-lug parts to swap on my car because, well, I had nothing else to do that day.

Like the 328i conversion page, I decided to break down the parts by type (brakes, suspension, wheels). There are a few ways to go about this conversion, like you can use E36 front struts, E36 318ti or Z3/M Roadster rear trailing arms, etc. but I wanted to use the stock E30 M3 parts because everything bolts right up with no modification or headaches. The parts I used are the M3 front strut assemblies, trailing arms, calipers, rotors, EBC brake pads, E32 750iL brake master cylinder, E36 Racing Dynamics 17" wheels, E34 5-series 15" spare wheel, and my existing Racing Dynamics swaybars/springs and Bilstein shocks.

BRAKES

DESCRIPTION PART # QUANTITY AVG $ NEW

AVG $ USED

Caliper, front left (complete)

34-11-2-225-403 1 125 50

Caliper, front right (complete)

34-11-2-225-404 1 125 50

Caliper, rear left (complete)

34-21-1-160-353 1 125 50

Caliper, rear right 34-21-1-160-

This site has no affiliation with BMW North America, BMW AG, BMW M GmBH, the BMWCCA, or Chris Bangle. Just so you know.

Optimized for 800x600 resolution or higher.

(C) Copyright 2003-2005 Strictlyeta.net

E36 5 Lug Conversion on an E30Why do it?

Bigger brakes

More wheel choices with E36 offset

Cheap conversion for bigger brakes front and rear

Ground Control makes modified strut mount housings with E30 M3 sway bar brackets

A few things you should be aware of when doing an E36 5-lug conversion on an E30:

E36 M3 struts\spindles\hubs and brakes are not the same as E36 325 or E36 328s.  They are not interchangeable.  I don’t know the specifics, but if you want E36 M3 brakes, you have to get E36 M3 spindles\hubs.  Get only E36 M3 suspension for the front

If you don’t want to do the conversion, Ireland Engineering (www.bmw2002.com) sells a couple of great brake conversions to be used with your existing E30 suspension.

I make many mentions of Ground Control (www.ground-control.com) suspension in this article.  I do not work for them, but fully endorse their products based on experience and workmanship.  The guys at Ground Control, in particular Jay and Dale, know BMWs, race BMWs and built these kits just for us car nuts.  They helped me custom tailor my suspension to my needs and put together the kit from my existing parts and new parts.

REAR:

318TI Rear Trailing ArmsYou need 318TI rear trailing arms.  I have read a few things online that the Z3 rear might work considering it is a modified E30 rear end, but I am not sure if the wheel offsets will work correctly.  With the 318TI, I used E36 17x8.5 M3 Motorsport wheels in the rear with 245/40 R17s.  They fit with a simple fender roll and no other modification to body work.

While you have the rear trailing arms out of the car, you should strengthen the sway bar bracket mounts with additional metal and welding.  The MZ3 arms are further strengthened.  See Xwebsite for more details.

Rear SpringsYou can re-use your existing springs because the rear hasn’t changed much.  I use Ground Control rear springs with adjustable perches. Jay at Ground Control recommended 800lb springs for my track use.  At first, I thought that was going to be to way too stiff.  But due to the geometry of the rear suspension and placement of the spring perches, it is the equivalent of a 400lb spring on other cars.  I had 450 rear springs before and I felt they bounced too much and I sometimes bottomed out.  With the new 800lb springs, I don’t bottom out at all and the rear is really tight.  I will also not be running a rear sway bar with these stiff springs and adjustable shocks. 

Rear ShocksGround Control is the exclusive distributor of Koni Externally Adjustable rear shocks for the E30 chassis.  I used to have Koni Internally adjustable shocks on my GTI many years ago and having to take the shocks off the car in order to change the shock dampening is a real pain.  Pay the extra money and get the externally adjustables.

Rear Sway BarSince my car is for the track, I got really stiff springs and won’t be running a sway bar.

FRONT:

M3 Front Struts\Spindles\Hubs\BrakesThe most important pieces are the front spindles and hub along with the brakes.  You can also use the M3 struts, but you may find yourself buying new struts if you are going to race the car or take it on the track.  The E36 struts include the housings not like the E30 which you use inserts and re-use your housings.  I used M3 struts with E30 top strut mounts to get everything bolted to the car and running.  I bought Ground Control shortened E36 M3 strut housing that took my E30 Koni adjustable front inserts.  Ground Control also sells a smaller diameter insert ‘cap’ that

won’t rub the small Eibach springs I am using.  The original cap you screw into the strut housing in just too wide and will rub on the springs under load.

E30 Top Strut Mount with E36 StrutYou need to use the E30 top strut mount to be able to bolt on the E36 strut to the car.  I started off using a simple rubber mount knowing that I am going to be using the Ground Control camber plates and solid spherical mounts.

’97 or ’98 M3 front control armsThese arms on the E36 go into centered control arm bushings.  This is critical because the geometry  is compensated in the control arm, not the bushing for these cars.  This geometry plus the offset bushing puts the wheel in the correct place for the e30 chassis.

Offset front control arm bushingsThese bushings along with the control arms mentioned above will give your e30 the correct centered placement of the wheel in the front wheel well.  I used E36 17x7.5 M3 Motorsport rims in the front with 225/45 R17s.  They fit great and you can see from the shot below how they are centered in the wheel well.

E36 Steering RackI used an E36 non-M3 steering rack as well when I did my conversion.  I had the engine out so it was a bit easier to do at that point.  My old rack was leaking and the E36 gives me a closer steering ratio.  The E36 M3 is ideal with an even shorter XbyX ratio. 

Steering rack StopsI am installing the Turner Motorsport steering rack stops to help prevent the rubbing of the wheels on the inside of the front wheel well.  When the wheel is turned to full-turn, the big wheels rub the chassis.  The steering rack stops should help stop this.

Links:E30S52 MainE30 S52 Build-upE30S52 BMW 318i page1E30S52 BMW 318i page2E30S52 BMW M3 page5-Lug Conversion5-Lug Conversion PicsE30 Suspension

E30 325is page

Ground Control Home PageZionsville Autosport Home Page

Speichers.com Home

AWESOME!!!

Use e36 M3 struts that way you can keep your e30 springs,(if you have them). The e36 m3 and e30 use the same size spring, whereas a basic e36 uses wide springs. You can use e36 M3 spindles for ///M brakes, but standard e36 325i brakes are sufficient, and in fact are so good on my car, I broke something in my SRS system :-/ didn't feel like paying money to fix it, so I unplugged the system.

So use e36 m3 struts, and e36 325i spindles/hubs/brakes. Also use your e30 spring hat, on the springs. Now in order to get your geometery back into e30 spec, your gonna need to do quite a bit of stuff, and by the time your done it will have cost the same to use e30 M3 stuff. But if your still interested, read on.

Use offset M3 control arm bushings. Get a new set of late model M3 control arms, as they have built in caster, which will push your wheel forward more.Without arms

With arms:

As you can see its still not perfect, but according to the alignment machine its within spec.

Alright, now that we have the caster straitend out, you have a camber problem...

A major improvement to help everything up front is to use bilstien sports. Factory m3 struts are garbage. Step one to correct the positive camber problem is to use, crash mounts. Something like a half of degree can be had with these. They are a factory part used incase a car was in an accident and had camber problems. That wasn't enough to bring it all back in spec. Finally we had a set of Ireland Engineering camber plates laying around. I threw them on there, and slid them as far in they'd go. This brought the whole camber problem very close to spec.

Now for the rear, it's cake! Simply get rear hubs from a early 4 or 6 cylinder model Z3, you will also need new rear bearings. Brakes are the same Z3 brakes and rotors. Thats it! you can use your existing struts.

Now for the small stuff. Wear sensors, your gonna use the stock rear sensor, and use a e28 front sensor. All your abs sensors are a direct plug and play. No modifications. Now you have e36 brakes, and a larger selection of wheels! Thats about it. Hope this helps. Aaron RhodesSports & Imports

M-Coupe Rear Trailing Arms

Pictures and part numbers supplied my Mike Krnc.

It is fairly well known at this point that BMW's M-Roadster and M-Coupe cars were designed with a rear suspension that is very similar to that of the earlier E30 series cars. This includes the E30 M3 of

course. That is the reason that the very popular M-Coupe rear differential cover bolts right on to an E30 M3.

However, it is becoming apparent that the M-Coupe suspension is not just similar to that on the E30 chassis, but is actually identical in many respects, such as angles and pick-up points. In fact is is possible that the M-Coupe / M-Roadster rear subframe and trailing arms may be a bolt on replacement for the standard E30 units. The only difference being the "ears" for the caliper mounts and the various brackets and fittings.

One of the main differences between the M-Coupe rear trailing arms and the earlier E30 arms is the factory addition of an "A-arm" type fortification between the two "legs" of the trailing arm. This was presumably done to strengthen the trailing arms so that they could cope with the much higher torque output of the U.S. and Euro spec M-Roadsters and M-Coupes. It is said that these U-shaped brackets are available separately from BMW dealers but I do not know the part numbers (this turns out to be false, they are not separately available - sorry). In any case, a look at these pictures shows that the brackets would be very easy to duplicate by any competent welding shop. In fact, a rectangular tube would function even better than this U-shaped channel, and would be easier to source. Make sure your welding shop knows how to weld a steel structure in such a way that the heat from the welding does not warp the part.

The red arrow in the photo above shows what I refer to as the M-Coupe "camber gusset". It is a separate fortification from the "A-arm" gusset/bracket. It is obvious from observation that this gusset was added to prevent high cornering loads from flexing the trailing arm and allowing the camber setting to change i.e. dynamic camber.

This camber gusset may also be available separately from BMW dealers (Ed. note: it's not). But as with the A-arm gusset, it is apparent that any welding or sheet metal shop should be able to duplicate this gusset with a minimum amount of effort.

Those in the mood to experiment might be interested in the following part numbers:

M Coupe subframe ($491 list) p/n 33 31 2 228 200

M Coupe subframe bushings (~$20 ea.)

p/n 33 31 1 090 946

M Coupe trailing-arm bushings (~$40 per pair)

p/n 33 32 9 058 822

M Coupe trailing-arms (~$300 ea.)

p/n 33 32 2 227 967 lt p/n 33 32 2 227 968 rt

Ed Note: I have discovered that the M Coupe subframe bushings will NOT fit the E30 chassis. They are too short. However, the M Coupe subframe itself may well fit our cars. The jury is still out on that one. The M Coupe trailing arm bushings WILL work on the E30 chassis - I did that. It should be noted that the p/n given above is for the eccentric trailing arm bushings, which can be used to effect about a 0.5° camber change to the rear wheels. The Parts CD shows that the p/n's for the M Coupe eccentric and regular trailing arm bushings are the same as those for the E30 chassis. So no increase in rubber durometer will be realized. Too bad 8^(

As requested:

Even before I bought my E30, I fretted over the 4 lug pattern and tiny brakes. Although the stock brakes never let me down (even after M50 power), I had a few close calls during emergency stops.

Most people who want to upgrade their E30�s brakes use E30 M3 parts. This is a great option since the swap is straightforward and the E30 M3 brakes can be replaced with E36 M3 brakes with some work. However you can also use M roadster parts as I have proved.

There is a lot of misinformation about this swap so I will try to clarify that in this article.

First let me list my complete setup:

FRONT E36 M3 steering rack (Zionsville Auto sport kit) E36 Tie Rods M roadster front hubs with brakes E30 front Stainless steel lines Bilstien E36 M3 front sport shocks H&R E36 front springs Stock E30 front strut mounts E30 M3 offset bushings pressed into modified control arm bushing brackets

REAR: M roadster trailing arms with hubs and brakes E30 rear Bilstien shocks E36 H&R springs or E30 H&R springs (both work, the E30 springs are lower) M roadster half shafts E28 diff output flanges

At this time I have two minor problems I still need to sort out.

1. The front wheel is not centered in the wheel well. It needs to come forward another � of and inch. It this never gets resolved it won�t be a BIG deal since the difference is not too noticeable. However, I may have trouble if I want to fit 18�s.

2. The rear brakes lines on the M roadster trailing arm are routed differently then the E30 rear trailing arm lines. I was forced to use E30 trailing arm lines zip tied to the M roadster trailing arms. Then I had to use an extra set of front rubber lines to connect the trailing arm lines to the caliper. I think the best fix will be custom Stainless steel lines that run from the caliper to the sub frame lines.

I should say I did not actually perform the conversion. I planned to tackle this all with my friends, but unfortunately a bad rear wheel bearing forced me to advance the date for this project, so I dumped off the car and parts at a friends house (an awesome BMW tech) and had him do it for me. However, I was involved in the process at all times and can probably answer any question about the swap.

In the front, everything is a direct bolt on. The only custom part is machined control arm bushings. These along with M3 offset bushings allow you to push the wheel forward in the wheel well. Without the offset bushing and custom bracket the wheel will sit towards the rear of the front fender and look out of place. Rubbing may also be an issue. As I said above, I still need to find a way to move the end of the control arms closer to the outside of the car as this will center the wheel in the wheel well.

In the rear everything also bolts right on. The M roadster trailing arms bolt right on to the E30 rear subframe. Many people ask about using an M roadster rear subframe. I have been told by a friend the M roadster rear subframe is slightly to narrow and will not fit.

Since the M roadster trailing arms are the same general shape as the e30 rear subframe, E30 rear shocks and springs will work. M roadster half shafts (also called axels) are used. These haflshafts will not connect to the stock E30 diff output flanges, but they will connect to E28 output flanges. The solution�press E28 output flanges into the E30 differential.

THE RESULTS

Wow! The car looks and feels amazing! The car rides like a new E46 (only with much stiffer suspension), handles like never before, and stops on a dime. I mean this thing stops! You know how good the brakes are on the 540i. Now imagine those suckers on a 2900 pound E30. The car still tends to pull slightly to the right, but this may be solved with an alignment. What surprised me most was how this car handles. The suspension is only slightly stiffer, but the car feels much more stable in corners. I can�t understand why this would be, but I swear to you there is a significant difference.

I�m currently running 17x7.5 E36 LTW replicas with a 41mm offset. They just clear the brakes. The rims do not extend as far out as I would wish so when I replace them, I will move to a deeper offset (35 maybe?).

Apparently the E30 and E36 bilstein sport shocks have the same valving so it does not matter I am running E36 in front and E30 in rear. The E36 H&R springs are slightly stiffer (200 front 380 rear) compared to the e30 (184 front, 350 rear). I�m currently running E36 all the way around, but the E36 rear springs have raised the rear end slightly, so I will probably use E30 springs in the rear. This should bring the car back to an even lowered stance. While the E36 rear springs raised the car in the rear, the E36 front springs and shocks actually lower in the front. I�ll probably eventually go with Ground Control Springs all the way around to get the perfect ride height.

While many like the M3 LTW replicas, I am not crazy about them and will replace them with a 5 star style rims as soon as I feel like spending some money. I�m currently considering:

17�: ACS III replicas ACS III (real deal) MVR Magmums (My favorite...currently trying to buy a two to see if they fit) Voxx/Mas MGR (again) Iforged or HRE (depending on what my friend can get me at discount)

18� (If I can get my front wheel centered and convince myself I won�t bend them) ACS type III M parallel replica for E36 Iforged or HRE

I want to avoid spacers at all cost as I despise spacers. Your feedback on rim choice and

fit is appreciated. I�d also like to hear your suggestions on my two problems.

I'd like to thank Lino and Derek357i for helping answer my questions. I'd also like to thank Chris for posting pictures of the E36 suspension conversion on E30.de as it helped me and my friend actually see what we needed to avoid.

Pictures will be in the next post

Modified Rear Subframe and Trailing Arms Page

1 / Page

2 Executed by Jake Larson

Background: E30 M3 owner Jake Larson shows us his modified rear subframe and trailing arms. The subframe has been modified to allow independent adjustment of rear camber and toe. Note that this is not possible with the popular K-Mac rear eccentric rear trailing arm bushings, where an adjustment in either camber or toe will also effect the other measurement. Click here for more information on the K-Mac rear trailing arm bushings and how they work.

At right and below we see the modification for toe adjustment on the rear subframe.

The eccentric bolt is actually a BMW E39 5-Series part:

p/n 33 32 1 092 310 bolt

(M12 X 1.5 X 98mm)

p/n 33-32-1-093-456 washer

Kits like these can be had from several sources. Or you can fabricate your own.

A study of these photos will reveal how there eccentric bolts work to adjust both camber and toe. The eccentric parts of the bolt and washer are held in position by the welded on tab. Then the hole in the trailing arm mounting point is slotted. Thus, when the

eccentric bolt is rotated, it ends up sliding the mounting bolt (i.e. pivot point) forwards/backwards or up/down (toe or camber).

Here we see the adjustment modification for camber. The principle is exactly the same as for toe, except that the slots are rotated 90°.

In this instance the camber adjustment is on the "inside" of the rear subframe, and the toe adjustment is on the "outside" of the subframe. But there is no reason really that this situation could not be reversed.

The nice part of this principle of adjustment is that camber and toe are decoupled. However, the negative aspect is that in moving the pivot points around, one is changing the roll center height, and also the camber/toe curves. The effect is unlikely to be all that great, but it was enough to force the BMW Motorsport factory racecars to implement the camber and toe adjustments on the trailing arm, so that the pivot points stayed fixed.

The last of the E30 M3 DTM racecars actually had an adjustment for roll center height, as well as for camber and toe. One can find a picture of this mechanism, as well as a description of roll center in a semi-trailing arm suspension on this page.

Page 2 - Modified Trailing Arms Page

1 / Page

2 Executed by Jake Larson

Here we see some photos of the modifications that Jake made to his rear trailing arms in order to stiffen them up. There is the well-known A-Frame modification that also comes on the M Coupe trailing arms. Also, the camber reinforcement, which can also be found on the M Coupe. And then a unique toe reinforcement that Jake came up with. I may have seen something like this on a shot of an E30 M3 rally car somewhere.

Click here to see some photos of the M Coupe rear trailing arms.

The E28 and E30 M bearings themselves are IDENTICAL. The hubs into which the bearings are pressed are different in the area that holds the ABS ring. This is because the cars use different strut housings /spindles and in order to be able to use the same ABS sensor unit on each, the offset of the ring on the hub has to be changed so that it aligns properly under the sensor. So when you use E28 hubs on an E30 M3 you change from the fine toothed E28 ring to the coarse toothed (half as many teeth) and you don't press the ring on all the way. You want the ring to be under the sensor so that a good clean ABS signal can be obtained. E28s are much heavier than E30s and have a higher front weight percentage and the hubs/bearings don't die prematurely.

On brakes, it's easy to change out the fronts and think you have made an improvement. This is because the now reduced pedal effort for a given rate of retardation can fool us. IOW the pedal feel can be great at low to mdoerate levels but when you so all out breaking the rear brakes don't help enough so the net stopping power is actually reduced. What matters is the max deceleration which can easily be reduced if nothing is done for the back of the car. This is one reason that Stoptech uses large front calipers and rotors which are matched to stock OR uprated rears via fairly small pistons. That way the front to rear proportion of braking is maintained or improved.

I'm using KVR four piston front calipers with stock rears, both over stock but drilled rotors (usually I hate drilled, preferring slotting). With track pads front and rear the car feels really reat..but stops take more distance than if I run mild front pads compared to the rears. At the moment I am running street semi-metallics up front and Porterfield R4-S out back. This setup more closely proportions my car to what it really needs. If you just slap on big stuff and ignore stuff like this you'll have too much of the braking coming from the front and not enough from the rear during all-out stops. Yes you need to get the proportioning right if you want to stop properly, and no ABS won't fix all of that.

Stan

Brake UpgradeContained in this document:  Brake Upgrades - E28,  Brake Upgrades - E34.  See also:                              Rotor Warp - Prevention,  Brake Upgrade - Master Cylinder.  

Brake Upgrades - E28  ( Note:  The following is a compilation from many posts .  Ed. ) 

The brakes listed below bolt on without any modification.  This requires calipers, carriers, guide bolts, rotors and pads.  You need the carrier for each brake system, usually included if you buy used.

Front brake assemblies that will fit any E28:(some numbers may be slightly wrong, I misplaced my table)E28 535 282mm x 25mm vented     or     E28 M5 300mm x 30mmE34 535 302mm x 22mm ventedE34 540 302mm x 28mm ventedE34 M5 315mm x 28mm ventedE34 M5 345mm x 32mm vented from 6/94E32 735 302mm x 28mm ventedE32 750 302mm x 28mm ventedE31 840 324mm x 30mm

Rear brake assemblies that fit any E28:E28 535 284mm x 10mm solid E34 535 300mm x 10mm solidE34 540 300mm x 20mm vented E34 M5 300mm x 20mm ventedE34 M5 328mm x 20mm vented from 6/94    Unfortunately these don't work, but are here as a size reference    E32 735 300mm x 12mm solid    E32 750 300mm x 20mm vented

The E34 Rear Brake Part Numbers to use: E34 540i / E32 740i Calipers:    34 21 1 160 399    ( part number - left )     34 21 1 160 400    ( part number - right )E34 540i / E32 740i Carriers:    34 21 1 160 384    ( part number x 2 )E34 540i / M5 300mm x 20mm rotors    34 21 1 159 659    ( part number x 2 )

E32 calipers need the E32 master cylinder to work properly.

If you install SS lines without bigger-volume piston'ed front calipers (IMO) the pedal ends up unacceptably 'sharp'.  However, ABS equipped cars can loose some of the spongy pedal feel by using SS lines.  

The E32 brakes will fit under 15" wheels. These are your best choice for economy... and will be capable of handling just about anything you would do with your 535i.  E32 750iL front rotors are vented from the inside rather than outside around the "hat". 

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% frontand 34% rear.  

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 Pads - E28To 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.  

Date: Thu, 31 Aug 2000From: Jerry Brown <jerbrown@pacbell.net>Subject: Re: [uuc] WNT e-28 big brake kit

Rob,

While it's true the stock brake master cylinder will *function*, I can

tell you from experience, that replacing it with the E32 750i piece*greatly* enhanced pedal feel and reduced pedal travel on my E24 with the E34 brakes.

But I suppose it's one of those preference things. ;^)

jerry

Rob Levinson - UUC Motorwerks wrote:> No, the E28 master cylinder is just fine. On my ex-535i Turbo, it's been running those> brakes for over two years and as far as I know the new owner still likes the brakes.> > The E28 M5 master cylinder, as a comparative example, has no problem running the 850CSi> 324mm front brakes and 540i 300mm rear brakes as in my car.> > Rob

_________________________________________________________

In the first upgrade iteration, I installed the E34 540i fronts and rears; the 300mm X 28mm (front) and 300mm X20mm (rear) is a *huge*improvement over the stock 284mm units. FWIW, the E34 540i calipers are the same as the E32 740i/750i, but differ in the rear rotor.

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

In addition, the E34 M5 calipers, carriers and rotors - both front andrear - 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 largerdiameter.-------------------------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'llneed to get a complete M5 kit, since the brackets are very difficult and

expensive to get separately.

My recommendation is to go with the 540i brakes, new Balo rotors andgood quality stainless steel brake lines. Don't forget to upgrade to the750i brake master cylinder.

Date: Fri, 02 Jun 2000From: "ra rabmw" <rabmw@hotmail.com>Subject: Re: [uuc] Date: Fri, 2 Jun 2000

Congradulations, Rod;The VERY last sentence.

After all that space, you and others finally got to the solution; the E32 calipers need the E32 master cylinder to work properly on most BMWs. Period. Write it down.

>From: "Rodney Moore" <m6bigdog@home.net>>Subject: [uuc] Date: Fri, 2 Jun 2000>>Jerry,>Since the upgrade you performed has been extensively reviewed and road>tested by many BMW enthusiasts, I would not think the upgrade caused the>brake performance difficulty you perceive. Yep, bleeding the brakes can be>tricky and I suggest multiple brake bleedings. I use the pedal bleed method>first followed by the pressure bleed method. Caution, pedal bleeding causes>small bubbles in the brake fluid that will take time to settle out. Pedal>bleeding will also make the master cylinder travel into normally unused>areas of the master cylinder. Pressure bleeding a system with an ABS, on>the other hand, may not expel bubbles trapped in the horizontal brake lines>going to the calipers. It's a tough life!!>>My diagnostic suggestions are the same.>It you think you have effectively bleed you brakes? Test for master cylinder>internal leaking with the boost accumulator discharged. Master cylinders>can leak internally(inner piston seal) and that will cause the brake pedal>to move toward the floor with time and there will be no indication of a>problem such as a brake fluid leak. Have the brake boost pressure regulator>tested. You may also want to have someone press on the brake pedal while>you investigate the flexible lines and other possible brake system components. >I have no experience with the ABS causing this pedal feel issue.>>My M6 has the same Master cylinder as your 635, 23.81mm cylinder bore. I>have upgraded to Euro 1995, E-34, M5 BIG brakes. The brake pedal has always

>had an appearance of wanting to depress to the floor with boost, however, I>will not press the brake pedal as hard as I can because it is possible to>damage components with maximum hydraulic pressure generated by the brake>systems under boost. Also the brake pedal support has been known to fatigue>and or fail under excess pedal application force. IMHO, Since the road>performance of my brake system is outstanding, I thing that is the ultimate>test and I personally refrain from suggesting, that the pedal feel when the>vehicle is stopped is an indication of a system failure.>>An increase in pedal firmness can be increased by installing the master >from the E-32, 750 that has a 25mm cylinder bore.>Regards,>Rod...>>----------original Message---------------->Date: Thu, 01 Jun 2000>From: Jerry Brown <jerbrown@pacbell.net>>Subject: Re: [uuc] RE: <E24/E28>: soft brake pedal>Rodney,>You make some thoughtful observations. However, one thing I didn't>mention is that the brakes in my 533i don't exhibit the same behavior:>the pedal is rock hard at all times. Also, this behavior was present>before I upgraded the calipers.>Thanks,>jerry>>Rodney Moore wrote:> > Jerry,> > It is possible the boost pressure regulator(on top of the accumulator/bomb)> > is faulty allowing excess boost. It is possible the master cylinder is> > bad (test by discharging the accumulator and holding the brake pedal> > depressed firmly until your leg hurts and if the pedal hasn't moved down> > toward the floor it's good).>--------snip------------>>Rodney Moore>BMW CCA #86830>Golden Gate Chapter>m6bigdog@home.net

Date: Tue, 29 Aug 2000From: "ra rabmw" <rabmw@hotmail.com>Subject: Re: [uuc] WNT e-28 big brake kit

HOWARD:The "big brake kit" best used is simply the master cylinder, calipers, and rotors, from the 735/750 E32 cars.  Straight bolt-on operation.  Calipers and perhaps master cyl. you can find used.  Have the new rotors (for all four wheels) gas slotted by a BMW or other repair/raceshop properly, add a good track/street pad set, and you can out-brake E28 M5's,E30 M3's, 540i/6's, small Porches, and just about anything else that isn't a newer "P" or BMW "M" car.  Those you can keep up with, but not out-brake.Ask me how I know.

Unless you have a turbo, or hot cam set-up (Hartge, Alpina, etc.), and/or run something at or over 300hp, that's all the brakes you should need.  You can upgrade the rears, but shouldn't find it necessary past the gas slots and pads.The Brembo system is terrific, but unnecessary for most E28's without the euro 296hp engine or better.

o/______\o "RA"/Bob G. (Oo=00=oO) []=****=[]

Malcolm Reitz wrote:

> The front brake rotors on my E28 M5 need replacing. I've been told> that the factory M5 rotors aren't necessarily the best option and> there are other BMW rotors or 3rd-party rotors that will work better.> However, I don't have the specifics on what other rotors will work.> Can anyone pass along more info or suggestions?> > Thanks,  > Malcolm Reitz > '88 M5

Date: Wed, 24 Feb 1999 From: Jim Moran <bavarian@youvegotmail.net>Subject: Re: <E28> M5 brake rotor options?

Use E32 750iL front rotors. They're 2 mm larger in diameter and 2 mmless thick and are a direct fit. They are vented from the inside ratherthan outside around the "hat". I have them on my M6 and have yet towarp them. Finally, they are cheaper than the stock pieces.

Jim Moran'88 M6

Date: Wed, 24 Feb 1999  From: "Rodney Moore" <m6bigdog@home.net>Subject: RE:<E28> M5 brake rotor options?

Malcolm,The problem with the E24 & E28 ///M brakes is not the front rotors it isthat BMW left the undersized rear rotors from the non-motorsport cars in therear. Hence the front brakes do most of the stopping. This can cause thefront rotors to warp under hard braking. I also don't believe the use of302x28mm, 750 front rotors is a good idea because you are effectivelyinstalling rotors warn by 2mm your car and the 2mm increase in diameter isof no consequence. Also since the rotor wear limit is a combination ofrotor and caliper design you will experience reduced pad or rotor wearlimits. The claimed advantage of front vs rear rotor venting is a myth.I believe the best upgrade is to keep the stock OE front rotors &pads (Energit 582EE) and also replace the 284x10mm rear rotors &calipers(35mm pistons) with the 300x20mm vented rear rotors, pads (Jurid 547FF) and calipers(40mm piston) used on the E34, M5. A bolt on job!!The stock E24 & 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% frontand 34% rear. While the numbers don't seem significant, let me tell you,this is a big braking performance upgrade. Just ask some one that has anE34, M5. This is the same bias that the E34, M5/ E31, 840 uses. The heatload in the rotors will be better distributed front/rear and applying moretorque into the rear suspension will reduce the amount the rear end liftsunder hard braking.

Believe me, you won't regret the additional expense!!.Also installing just larger front rotors and calipers from an E34,M5(315x28mm) or E31, 840(324x30mm) rotors will only further increase thefront bias and increase the likely hood of warping the front rotors.

Regards,Rod...M6, with the E34, M5 rear rotors & calipers.E34, M5

Date: Thu, 25 Feb 1999 From: "Jake Steijn" <Jacob.Steijn@dol.net>Subject: Re: <E28> M5 Rotors

Malcolm,

The 750 rotors fit and are a good replacement, slightly lower cost, slightly

thinner (for better cooling) and with a different air flow (again, bettercooling). The M5 rotors are better for prolonged high-speed (100MPH+)touring due to air flow directed over bearings - not an issue in the US.

You can get them from the Ultimate Garage. I know, I just got mine.

Jake Steijn88 M5

Date: Thu, 25 Feb 1999 From: "Rob Levinson" <always_coca-cola@msn.com>Subject: Re:<E28> M5 brake rotor options?

>From: "Curt Kiser" <curtkiser@hotmail.com>>Subject: RE:<E28> M5 brake rotor options?>I like this idea. And it's a direct bolt-on?>I'd like to hear more about this from folks that has done it. Pro's &>cons to this mod. TIA.

Curt, buddy - where have you been? This is the upgrade you saw onHelen!

These brakes listed require no modifications and are completely reversible.You need calipers, carriers, guide bolts, rotors, pads.

Front brake assemblies that will fit any E28:(some numbers may be slightly wrong, I misplaced my table)E28 M5 300mm x 30mmE34 5-series 284(?)mmE34 M5 315mm x 28mmE32 7-series 302mm x 28mmE31 8-series 324mm x 30mm

Rear brake assemblies that fit any E28:E34 5-seriesE34 M5 300mmx20mm

Rob Levinson

Date: Sat, 22 Apr 2000From: "Rob Levinson - UUC Motorwerks" <rob@shortshifter.com>Subject: Re: [uuc] E28 Brake Options

(from memory but numbers should be accurate):

Stock E28 front brakes:282mm x 25mm

E32 front brakes:302mm x 28mm

Don't forget E34 M5 front brakes:315mm x 30mm

E31 840i/850i front brakes:324mm x 30mm

No tricks or pitfalls, all these systems bolt right up. You need thecarrier for each brake system as well, usually included if you buyused.

The E32 brakes will fit under 15" wheels. These are your best choicefor economy... trust me, they will be capable of handling just aboutanything you would do with your 535i.

The E31 brakes will fit under 16" wheels. These may be overkill butif you can find a set cheap... well there's no such thing as too muchbrakes! Actually, that's not entirely true. The E31 brakes willunbalance your braking and you will be wanting to do a rear upgrade toE34 540i brakes as well.

Rob Levinson

Date: Sat, 22 Apr 2000From: Ethan Stock <ethans@netwiz.net>Subject: [uuc] Re: [E28] brake upgrades

Chris said:

>The time has come to do the front brakes on my '86 535i...>I'm looking to do a relatively affordable but beneficial upgrade without >going overboard on aftermarket performance parts.

And Rob replied:

>(from memory but numbers should be accurate):

>>Stock E28 front brakes: 282mm x 25mm>E32 front brakes: 302mm x 28mm>Don't forget E34 M5 front brakes: 315mm x 30mm>E31 840i/850i front brakes: 324mm x 30mm>>The E32 brakes will fit under 15" wheels. These are your best choice>for economy... trust me, they will be capable of handling just about>anything you would do with your 535i.>>The E31 brakes will fit under 16" wheels. These may be overkill but>if you can find a set cheap... well there's no such thing as too much>brakes! Actually, that's not entirely true. The E31 brakes will>unbalance your braking and you will be wanting to do a rear upgrade to>E34 540i brakes as well.

My notes:

1) Stock 535i are 284x25mm front (vented) 284x10 rear (solid)2) I believe that 540i/6 fronts are the same 315mm x 30mm as the E34 M5,and may be considerably cheaper.3) A front upgrade is all you really need, unless you're *very* serious atthe track (not likely with an '86 535i?) I had overheated the stockfronts only once or twice on the street, in really hard-core situations(racing down a twisty mountain road in Santa Fe... had to translate both3000 feet of altitude and my excess enthusiasm into heat via the brakes...they were fading fast!)4) You may also find E28 M5 brakes around, at 300 x 30mm fronts... theseare often expensive because they are 4-piston calipers, one of the few thatBMW made. I know people that swear by the superior feel, but BMW itselfwent back to single-piston calipers for the E34 M5 and the E36 M3. Youdecide. Either way, the E28s are a valid upgrade. BTW, the E28 M5 usedthe same rear rotors as the 535i. Which should tell you how important rearbrakes are in the big scheme of things. 5) Personal experience: E34 M5 fronts will indeed fit under 16" wheels,but I recommend that you get SS lines to go with them. They have a largerpiston volume than the old fronts, and you will really notice the pedallagging a bit if you still have the old lines. Conversely, if you installSS lines without bigger-volume piston'ed front calipers (IMO) the pedal onthe E28 ends up unacceptably 'sharp'.6) These are indeed all bolt-up: E28, E34, E32, E31, and (pretty sure)E39 brakes are all mix and match. 7) Just checked my database: The 8-series (E31) 324x30mm are also 4-piston. 8) If you really want to go nuts, the Euro 850Csi were for a long time(pre-E39 M5) the biggest BMW brakes... 345x32mm. These also bolt stock toan E28. Just ask Sherman 'big brakes' Koo here in the GGC. They do take

17" wheels, though, and (again IMO) you start making unacceptableride/handling tradeoffs on the E28 with 17" wheels because of therelatively small overall wheel diameter. 9) Noting that the E28 M5 are 300x30 and the E32 are 302x28, if you do getthe E28M5 fronts, you can run E32 rotors... the extra 2mm of diameter fitsfine, and they just start out as if they were 2mm worn. There used to beextensive debates back when the E28 M5 was newer about the different hubconstruction of the two rotors, and whether one rotor or the other bettercooled (or insulated from heat) the front wheel bearings. Both were big,fast cars... I don't think it really matters. 

Also: Rob has a great web page out there somewhere where he details the540i rear brake install... which I coincidentally just asked him for a URLto... Rob? maybe move it under UUC projects? 

Cheers,Ethan88 535is moderately tweaked

Date: Thu, 25 Feb 1999 From: Jerry Chyo <jkchyo@redshift.com>Subject: Re: E28 M5 brakes

Rod wrote:<M5 brake problems snipped>>I also don't believe the use of 302x28mm, 750 front rotors is a good idea because >you are effectively installing rotors warn by 2mm your car and the 2mm increase in >diameter is of no consequence. Also since the rotor wear limit is a combination >of rotor and caliper design you will experience reduced pad or rotor wear limits. >The claimed advantage of front vs rear rotor venting is a myth.

I'm not sure I agree with this. Many have had very good results changingto the E32 rotors, and the venting issue is real. Frank Fahey (of ///Mfame) has even developed a cover for the hats that effectively changes theflow of air to do what the E32 rotors do.

>I believe the best upgrade is to keep the stock OE front rotors &>pads (Energit 582EE) and also replace the 284x10mm rear rotors &>calipers(35mm pistons) with the 300x20mm vented rear rotors, pads(Jurid 547>FF) and calipers(40mm piston) used on the E34, M5. A bolt on job!!

This is a great upgrade, albeit a little more expensive. It's harder tofind used E34 rear brake setups than you would think (there were only a fewK imported into the US). Do the regular E34's have vented rotors in the

back? Would this be another alternative? Something not mentioned is thatthe fronts have 4 pistons and the rear have two. The E34 M5 caliperspistons are pretty big compared to the stock E28 calipers. I would alsochange the pads to Deluxe or Metal Master. They stop better than stock,cost about the same and don't dust as much.

>The stock E24 & 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. While the numbers don't seem significant, let me tell you,>this is a big braking performance upgrade. Just ask some one that has an>E34, M5. This is the same bias that the E34, M5/ E31, 840 uses. The heat>load in the rotors will be better distributed front/rear and applying more>torque into the rear suspension will reduce the amount the rear end lifts>under hard braking.

I can further comment on a full E34 M5 brake upgrade (at least the earlierE34 M5's. The later ones had HUGE front rotors). This setup will stop youon a dime. I have better brakes on my M5 (E34 M5 rotors & calipers w/MetalMaster pads) than my 6000 lb. Explorer. I feel very confident that I canmake any stop needed with this setup. It would probably be a great tracksetup if I ever took this car out, although the cost of the rotors is a lothigher (can you say TWICE what the E28 M5 rotors cost, and the E28 stuff isa lot more than the E32 stuff).

Sorry for the length. Hope it's helpful though.

Jerry Chyo'88 M5'72 tii

Date: Thu, 25 Feb 1999From: Sherman Koo <Sherman@facilitecture.com>Subject: Re: <e28> M5 brake rotor options?

------- Rodney Moore's email included: ------->The problem with the E24 & E28 ///M brakes is not the front rotors it is>that BMW left the undersized rear rotors from the non-motorsport cars in the>rear.Actually Rodney the problem with e28 M5's IS the front rotors. M5 rotors have holes in the hat to reduce weight. As stated by others, these holes allow air to escape horizontally rather than flow through the rotor. It has little to do with high-speed driving, brake bias, sweep area... as others have guessed.

But I do agree that the rear brakes are undervalued. I have four piston front calipers with 345 mm rotors on my M5. With the stock 284 mm rears, the car stopped very well. But when I went to vented 300 mm, it stopped absolutely flat; it was wonderful. So good that I'm hoping to install 328 mm rotors and calipers. 

Sherman Koo

______________________Facilitecture (sm), Inc.(510) 653-7151

Date: Tue, 13 Apr 1999  From: "Gilbert, Clark" <Clark_Gilbert@fmi.com>Subject: RE: E28 Brakes

Now we find that a host of brakes will fit onto an E28 with little or nomodification. The major variables then become rotor diameter, pad area, thenumber of pistons in the caliper, and cost. Larger diameter gets more stopping leverage, but going from 284 mm dia to 302 mm dia increases thelever arm by only 6%. More pistons look cool, but I don't know the effectivearea of the setups, so I can't compare the reduction in pedal force requiredfor the same pad application pressure. Therefore, the E32 brakes get my votebecause of the larger swept area, especially if you factor in cost: used E32calipers can be had for $75, used M5 or M6 4-piston calipers go for $500.

Clark87 535is

Date: Wed, 26 Jan 2000From: Gary Bossert <gary@bimmers.com>Subject: [uuc] Re: Audi (warning, not a lot of BMW content)

Steve,

Snip...

>(6/99- SportAuto did a comparative test of stock vs Movit brakes on>an Audi 1.8TT. They did consecutive high speed stops with each setup, cold>and warm from 200km. With the stock brakes, the first stop from 200km/h>yielded rotors temps of 417C front & 278C rear.....the Movit brakes were>150C front & 97C rear. By the time they did the 5th stop from 200km/h, the

>stock rotors were at 600+C both front and rear with flames coming front the>front hub assembly...testing was suspended. With the Movit brakes at the>10th consecutive 200km/h stop, rotor temps were only 356C front & 169C>rear. Now this really doesn't mean much here in the states as there's>little chance these cars will be driven at drivers schools where you'd be>doing this kind of high speed braking. It is significant in Germany.)

It's not even significant in Germany. Who makes consecutive stops from 124mph time after time ANYWHERE?Five stops from 124mph without a chance for any cool down time, you don't even have those extremes on the track (at least any track I've been to).Big brake kits are great for the track but a total waste on the street unless the motive is to look cool. I've yet to see anyone use up stock brakes while out for a drive on public roads, if so, they should be locked up.The brakes on both my '95 M3 and my S4 are both fantastic on the street with the edge going to the S4's twin piston 4 pad units. They are fantastic.On the track I'm sure they both need upgrading with Pads at a minimum and possibly a big brake kit to get the last little bit of performance.

Snip...

Gary BossertMany BMW's a few Audi's

Brake Upgrade - E34Date: Tue, 26 Sep 2000From: "ra rabmw" <rabmw@hotmail.com>Subject: Re: [uuc] Calling the big brake experts....

Felix;Based on Rob L's experience with E39 brakes for E34's,try this:

On my E34 535i, I had original size rotors gas slotted in a race shop (NOT bought from someone who may know how, but someone who did), added  super blue fluid, and installed a street/track carbon-kevlar pad set. (or use similar)

My car out-braked 540's at NHIS, and was the only 5 series, up thru E34 M5's, of any year, that had the same brake reaction times as the M3 Lightwieghts at O'fest '96 trials run by The Car Guys there.It also outdid the M3's at the April '97 Instructor's school run down here at Moroso Park.You don't need E39 brakes on your sister's car.

o/______\o "RA"/Bob G. (Oo=00=oO) []=****=[]

  ( Note:  This may not be suitable for the street due to the pads not                working well until they've had enough time to warm up.  Ed. )

Date: Mon, 3 Jul 2000From: "Rob Levinson - UUC Motorwerks" <rob@shortshifter.com>Subject: [uuc] <E34> dammit - big brake conversion didn't work.

As some of you may know, I have a brake upgrade fetish:

my '85 535i Turbo got E32 750 front brakes.

my '88 M5 Turbo has 850CSi brakes front, E34 540i brakes rear.

my '90 Miata (stop laughing) has larger '95 front brakes.

I wanted something more interesting for my '94 M5 Touring (stock front brakes are 315mm,single piston). The opportunity presented itself and I acquired a set of front brakesfrom the 2000 E39 M5. These use 345mm rotors (same size as the '94-'95 M5 Nurburgringbrakes) and larger single-piston calipers.

As apparently all BMW "big car" brakes since 1982 (E24, E28, E31, E32, E34) areinterchangeable, I bet that there was a good chance these E39 brakes would also.

Today was the day I was going to fit them. Took one side of the E34 apart and comparedthe parts. It was immediately apparent there were minor differences and fitment broughtto light major differences. BMW has deliberately made no part of the E39 brakesretrofittable. Bastards!

Differences:1) Hex-head screw that holds rotor to hub is in different spot.2) E34 rotors have two large holes with corresponding posts on hub - E39 does not haveholes so rotor cannot sit against hub.* Normally #1 and #2 would not be a problem as correct 345mm E34 rotors could besubstituted. BUT...3) caliper carrier holes for bolts that hold it to back of hub are about 2mm furtherapart. No chance of getting it to fit.

So the search continues for big brakes. Hmmm, doesn't the E38 7-series use 340mm rotors?

Anybody got a spare set of E38 brakes I could try?

Rob Levinson'94 M5 Touring'88 M5 Turbo

Date: Mon, 3 Jul 2000From: "Rodney Moore" <m6bigdog@home.net>Subject: RE: [uuc] <E34> dammit - big brake conversion didn't work.

Rob,The E-38, 740 has 324x30mm rotor w/single piston floating caliper front,324x12mm solid rear rotors and the 750 has 334x32mm rotor w/2 pistonfloating caliper front, 328x20mm vented rear rotors.Not only that the calipers on the E38 & E-39 mount rear of the strut.Previous models have the calipers mounted in front of the struts. Thiswould cause the E-38 & E-39 caliper bleed and flex-line holes to be on thewrong end of the calipers for the early model application. Also, if the 4piston calipers have small lead pistons (common on fixed 4 piston calipers)they can not be swapped left to right because then the lead pistons will bethe bigger ones and that will cause the pads to wear at a taper.

Maybe BMW anticipated the up-graders and made the mounting changes toprevent an inappropriate use of these parts on the earlier models?

Rod...

Date: Wed, 05 Jul 2000From: "ra rabmw" <rabmw@hotmail.com>Subject: Re: [uuc] Re: big brake conversion - too much brakes?

I don't know, guys...Spending a lot of time with E28's, most driven very hard need the 7 series update to work well, but the E34 cars start with a far better system, not far off the E32 brakes added to the E28's.  I have found in 80% of the cases, just gas-slotting the harder rotors and better pads is plenty of brakes for most hard E34 drivers.Of course, that doesn't apply to Rob, myself, or similar fanatics, who continually will try for 110% of a car's limit's in all categories. Still, my E34 535i would run The Glen for three days, and NHIS for two, never running out of brakes set that way (track pads for schools) at even my lead-footed braking maneuvers.  And I only use the PBR Deluxe pads for the street.

o/______\o "RA"/Bob G. (Oo=00=oO) []=****=[]

From: "Steve D'Gerolamo" <steved3@idt.net>Date: Wed, 30 Jul 1997Subject: E34 Brake Upgrade

>From: "Jeffrey R. Taylor" <j_taylor@anet-stl.com>>Date: Tue, 29 Jul 1997>Subject: E34 Brake Upgrade>>Hi all>> It is getting about that time where I need to replace my brake pads and>turn the calipers. I am considering upgrading my braking system while I>was at it. I called Dinan, but the only upgrade they had available was a>complete replacement of the entire system to the tune of about $5k.>> I decided that is definitely not the way I want to go. I was looking in>the Bavarian Autosports catalog and they have some cross drilled rotors>that will evidently fit my car. They say for off-road use only, which>doesn't seem like it would matter. I suppose I should just be happy with>what I have (which is actually pretty darn good).>> Does anyone have any experience with this, or any suggestions?

I'm in the process of upgrading the brakes on my wife's 89 535i with new front & rear 750i calipers and rotors. This will give the same braking as the 540i (E34)...the booster and brake m/cyl are no larger in the 8-cyl car. Not only are the rotors thicker but the piston diameters are larger in the 750i/540i calipers. The rotors are also vented in the rear. Appears to be a direct bolt on (you will need to buy the braker carriers as well). I'll follow-up with a racap of all of the parts, tools and fasteners needed to do the job once I've gone through the installation. SD

(BTW...I'd avoid the cross drilled rotors. They do not offer any significant performance improvement, mainly cosmetic appeal. The ATE slotted rotors would probably be just as effective at removing gases as the more expensive drilled rotors.) 

Steve D'Gerolamo The Ultimate Garage, Emerson, NJ Tel 201-262-0412 <steved3@idt.net> http://www.ultimategarage.com