Rear brake upgrade: 323i to E30 calipers

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Re: Rear brake upgrade: 323i to E30 calipers

Post by bmw e12 e21 »

I Have found a FERODO DS2500 set(FCP2H) wich has only the hight different then the original 323i rear pads.
The front DS2500 for e21 are for sale so no problem.
I am going to dremel the difference away and fit them to my 323i calipers.
The M315 wil get e30 calipers rear and VOLVO 240 TURBO calipers on front.


grt Remy

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Re: Rear brake upgrade: 323i to E30 calipers

Post by petroscf »

uwbuurman wrote: Sat Oct 17, 2020 8:30 pm Just buy a set of e30 calipers and have the brackets machined.
Well, if I find one I 'll buy one :thnx
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Re: Rear brake upgrade: 323i to E30 calipers

Post by mcjjordan »

mcjjordan wrote: Fri Oct 16, 2020 9:56 pm So im doing e30 rear calipers , need to machine down carriers .
Can anyone confirm what width they need taking down to?
Ive read to different readings!
I found one post said .580 which is 14.7mm
Then this one said 14.3mm
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Re: Rear brake upgrade: 323i to E30 calipers

Post by Jeroen »

Yes that's weird. Measurement shown on the photos in the 1st post is my own measurement and as far as I can remember that made it centered perfectly. But you can of course easily measure yourself with your own bracket to be sure. Perhaps something was off somewhere. The brackets I used were modified by a friend, he did 10 sets back then and he is used to precision metalwork (he is a clockmaker).
Regards/groeten, Jeroen
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Re: Rear brake upgrade: 323i to E30 calipers

Post by mcjjordan »

Thats good enough for me
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Re: Rear brake upgrade: 323i to E30 calipers

Post by uwbuurman »

I have a set from that batch to, fits like original. Be sure to grind off that notch in the middle also.
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Re: Rear brake upgrade: 323i to E30 calipers

Post by mcjjordan »

On a side note - ive got the original calipers left, theyre in need of a major refurb ..
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Re: Rear brake upgrade: 323i to E30 calipers

Post by Atle_323i »

If I upgrade the rear brakes with E30 calipers, do you need to upgrade front calipers aswell, to avoid rear brakes beeing to aggressive, and making the car unstable during braking? Or will E30 calipers work fine with stock front calipers?
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Re: Rear brake upgrade: 323i to E30 calipers

Post by Manitoba »

I am planning on doing exactly the same upgrade in the next few months. I am not a technician myself, but I've been told that e30 callipers at the back work fine with factory brakes front.

Let's keep each other posted, good luck!

Greetz,
Walter.
Last edited by Manitoba on Mon Jan 10, 2022 8:10 pm, edited 1 time in total.
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Re: Rear brake upgrade: 323i to E30 calipers

Post by uwbuurman »

I have the e30's rear and oem 323i e21's in front, works fine. And here's why: the oem e21 rear calipers are actually a bit undersize. So the brake balance is not optimal. By putting slightly more brake pad on the stock discs you'll get rid of that. So the balance is much better. And the e21 323i discs in the rear are exactly the same as the e30 325i ones.

Last argument: new flex brakelines are hard to come by, for the e21. The e30 calipers solve that, as the use different lines, which are a straight swap. The e30 lines are available everywhere

So you'll need:
Complete set of e30 calipers rear,
Adjustment to the brackets
New flex lines to calipers
Preferably a set for refurbishment of the calipers.
It's the man next door!

1978 BMW 323i
1980 BMW 528i maior restitutio
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2015 BMW 320dA touring xDrive High Executive ///Msport
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Re: Rear brake upgrade: 323i to E30 calipers

Post by petroscf »

Will E30 rear calipers match with 323i (E21) brake hoses? Or should these be replaced as well?
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Re: Rear brake upgrade: 323i to E30 calipers

Post by Atle_323i »

petroscf wrote: Mon Jan 10, 2022 8:25 am Will E30 rear calipers match with 323i (E21) brake hoses? Or should these be replaced as well?
You just need to replace those flex brake lines from caliper to first joint.
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Re: Rear brake upgrade: 323i to E30 calipers

Post by Atle_323i »

uwbuurman wrote: Sun Jan 09, 2022 11:46 am I have the e30's rear and oem 323i e21's in front, works fine. And here's why: the oem e21 rear calipers are actually a bit undersize. So the brake balance is not optimal. By putting slightly more brake pad on the stock discs you'll get rid of that. So the balance is much better. And the e21 323i discs in the rear are exactly the same as the e30 325i ones.

Last argument: new flex brakelines are hard to come by, for the e21. The e30 calipers solve that, as the use different lines, which are a straight swap. The e30 lines are available everywhere

So you'll need:
Complete set of e30 calipers rear,
Adjustment to the brackets
New flex lines to calipers
Preferably a set for refurbishment of the calipers.
Thanks for the feedback. I got it all covered, just need to machine and drill the bracket, and order new flex lines. :D
BMW E21 318 76 ---> transforming to 323i
BMW E21 323i 79 - gone to heaven
BMW F46 220D Xdrive daily driver.
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