Bigger e34 Brakes- update info

[genphreak]

I've been doing some research, dug up some new stuff so I thought you all might like to know.

Did anyone know that some e32s use a 12mm solid rear disc? I've never seen it mentioned but perhaps this is why there is some misunderstanding re e32 rear components (I keep seeing people trying to sell e32 rear calipers that will not fit e34 on eBay). I expect that it is impossible to make parts from the cars that come with the 12mm setup (ie 735i/il) fit an e34 as it never had a 12mm rotor and one cannot use the e32 rotors on the e34- I've never seen why not, but suspect it is a mounting difference- perhaps they widen the track or simply don't fit? Is there a hub difference... hmm more squirrelling required on realoem perhaps...

Anyway I wanted to clarify all this and in doing so I found that Bruno's page could do with a little update, so have sent him the table below, and hopefully he will. Any comments (especially on inaccuracies and additions) would be appreciated by me, Bruno and everyone that ever decides to do this to their car...

BEWARE- Below are 2 images crammed into 620x280/19.5kb of space-
The first is for the front brake parts and the second (below) for the rear brake components.

I have suggested to Bruno the following clarification on Rear Brake upgrades:
E32 rear rotors will not fit the E34. However the 750i/il, 740i/il (and 540i) calipers and carriers can be bolted on the E34 when used with 540i rotors. No E31 rear calipers fit the E34 but the 324x12 non-ventilated rotor does. Everything in the table will fit (except where stated):

I didn't look into the M-car brake components much (I was just researching the e32/e34 part similarities) as I have no experience with them and I thought that Bruno would (no-doubt) have them very well covered in his page already.

Nick

btw Erich, there is one version of the 750 (made only for the Japanese market) that uses a slightly different front brake arrangement than the rest- and I didn't add it as it is not applicable to any others... and no doubt you know which one already..

[angrypancake]

Random addition that wont really affect anyone: Alpina B10 Bi-turbo fronts, 4 piston calipers and massive rotors, 332x30mm. Don't know the part # but a full set (f & r) is $4,750 + shipping for calipers/rotors. Or you could get the set on German ebay right now, fronts... currently 101 euros. Needs 17" wheels or more (tight squeeze on 17's).

But seriously, thank you Nick, I am always scouring that chart.

[Kalevera]

Later (=>'91, I believe) euro E32 750s came with 4 pot front calipers, similar in appearance to the nurburgring units. I'm relatively certain this info isn't in realoem, but it should be in the most recent version of ETK. They're relatively inexpensive, I saw a 4 spot set go for ~ 300 euro on ebay.de recently.

best, whit

[genphreak]

Random addition that wont really affect anyone: Alpina B10 Bi-turbo fronts, 4 piston calipers and massive rotors, 332x30mm. Don't know the part # but a full set (f & r) is $4,750 + shipping for calipers/rotors. Or you could get the set on German ebay right now, fronts... currently 101 euros. Needs 17" wheels or more (tight squeeze on 17's).

But seriously, thank you Nick, I am always scouring that chart.

NP, dude, it's expensive business this brake upgrade stuff so the research is vital.

Everyone likes good data!

You know it'd be great if you could provide us all the part numbers for that killer kit you have

Goign off Bruno's charts (reading them without checking up properly) I managed to buy an incorrect set of rotors just now, so am sending them back unless someone wants to get a new pair to suit a 520/525/535/730 pair from me cheap- I'm in the middle of Sydney, Australia...

[genphreak]

Later (=>'91, I believe) euro E32 750s came with 4 pot front calipers, similar in appearance to the nurburgring units. I'm relatively certain this info isn't in realoem, but it should be in the most recent version of ETK. They're relatively inexpensive, I saw a 4 spot set go for ~ 300 euro on ebay.de recently.

best, whit

Thanks Whit, yes I haven't got the data on that but we should have it in there. The e38 4-pot calipers fit too I hear, if one redrills the bleeder since they go on behind the rotor instead of in-front of it as they do with the e38. Also one has to add a simple plate or bracket (or so I hear)... All this would be great to add in there...

[Kalevera]

The E38/E39 have a different carrier width, so they'd need adapters.

I'm confused on the drilling of the bleeder -- all factory four pots that I've seen have two bleed screws per caliper and a pressure line between the two halves on the opposite end. I don't see how it could interfere with the front or back of the caliper. I've not come across a set of E38 4pots, but they're the same brembo aluminum blocks as the E31 units with a different bolt width from what I can tell.

best, whit

[genphreak]

The E38/E39 have a different carrier width, so they'd need adapters.

I'm confused on the drilling of the bleeder -- all factory four pots that I've seen have two bleed screws per caliper and a pressure line between the two halves on the opposite end. I don't see how it could interfere with the front or back of the caliper. I've not come across a set of E38 4pots, but they're the same brembo aluminum blocks as the E31 units with a different bolt width from what I can tell.

best, whit

Sorry maybe I interpreted others wrongly on this Whit, are you saying one just has to swap a bleeder over with an existing plug when mounting them behind the rotor instead of in-front of it? In terms of the mounting holes and carriers, Erich's friend in Malaysia has been saying that a plate can be fabricated (easily) to make them fit, it worries me as he could be saying that to cusztomers that are incapable of fabricating their way clear of a speed hump, let alone modifying a high performance (and life-threatening) brake system...

[angrypancake]

NP, dude, it's expensive business this brake upgrade stuff so the research is vital.

Everyone likes good data!

You know it'd be great if you could provide us all the part numbers for that killer kit you have

Goign off Bruno's charts (reading them without checking up properly) I managed to buy an incorrect set of rotors just now, so am sending them back unless someone wants to get a new pair to suit a 520/525/535/730 pair from me cheap- I'm in the middle of Sydney, Australia...

i wish i did have it. but it's really not necessary, i dont track/race, and therefore can't justify buying a set of brakes that cost more than what i paid for my car..

part no: 34 00 617 from the alpina parts website.

there is a couple in socal that import alpina parts to the US, theyre pretty cool. front lip is $1,015 without paint. they have an overstock though of cloth, selling it for like 20euro/meter. could be a fun project for some crappy seats or a headliner.