Brakes and calipers

Post your E12 technical questions and comments here. Please, no off-topic posts.

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TernandoFoledo
Posts: 9
Joined: Sun Jul 16, 2017 3:34 pm

Brakes and calipers

Post by TernandoFoledo » Tue Mar 05, 2019 10:07 pm

Hey people, how are you?

So i've been looking around here, and many other places, but couldnt find many info about the brakes, as I needed. The other topic I've opened helped a lot - thanks to everyone that took part there :D - but i still have some crucial doubts

With that in mind, I would like to open this topic so we can discuss them a little bit :)

My main doubts are:

- my car is a 74 520, with front disks and rear drums. With the original calipers and a 15" wheel, whats the max rotor size I can fit? 286mm?

- my calipers need some spacers to go 25mm vented disks, or they fit them "stock"? Or do i need another part for this? Another calipers from newer models?

- the rear, to adapt some calipers, will need any special care? I noticed that the rear trailing arm is different from drums and disks models, which got me a little confused. I thought that it would be just swipe a bracket there, the plate and calipers.
Since the e28 swap is a little out of option, I'm thinking the e34 calipers, since my wheels are from the 540.

Im after a better stopping power and considered wilwood and other stuff, but with a 4pot original caliper, I thought to improve it and try the best on that platform. Would anyone recommend anything different?

Im all ears :)

Thank you very much!

Best,
Fernando

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Mike W.
Posts: 2398
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: Brakes and calipers

Post by Mike W. » Fri Mar 08, 2019 10:16 pm

You can't go to a significantly larger rotor with the stock calipers. Nothing else besides E12 (well, E3 also, but E12s have bigger brakes) fits E12s. Drill on down in Realoem to see what came on what. Likely your best and easiest upgrade will be to find brakes off a later E12 that are 280X22 front rotors. E28 brakes do not fit. E23 brakes are more similar to E12, but not much larger and they don't fit either. Technically M535i brakes from the ultra rare E12 M535i are 25MM thick and better, but no larger in diameter than many later E12s such as 528s. A bit better fade resistance, but that's all.

Nothing else fits E12s without a lot of machine shop work.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

TernandoFoledo
Posts: 9
Joined: Sun Jul 16, 2017 3:34 pm

Re: Brakes and calipers

Post by TernandoFoledo » Sat Mar 09, 2019 3:49 pm

Arent we blessed then? Hahhahaha

Well, that settles it. The 4pot caliper is the only thing that calms my nerves. I will stick to the original 520 rotor (or there is another one thats better and doesnt need a adaptation?) And work in the pads and fluid.

Thanks a lot Mike!

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