rear DRUM to disc conversion?

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pihlen
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rear DRUM to disc conversion?

Post by pihlen »

Hi,
I know there is a lot of info on swapping brakes, in the front, both for Volvo 240 brakes, Wilwood, etc. Also I´ve seen info on how to upgrade the rear discs (eg 323i) to other discs. However, my question, which I´ve had hard times finding info about, is how to swap rear DRUMS to discs.

My goal is to upgrade my brakes and have aimed at Volvo 240 calipers in the front with the Mini Cooper 276 mm discs. I have rear drums and can´t find good info about that. Anyone knows a good info source, or could create one? :) Are Volvo 240 rear calipers/discs a good option? How much/what re-build work does it take, etc?

Thanks in advance,


Always thankful for y'alls knowledge and help! (So far I guess I´ll get more help then being able to help out my self..so far) :)

Stefan from Gothenburg, Sweden.
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petroscf
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Re: rear DRUM to disc conversion?

Post by petroscf »

In order to do the conversion, I swapped my rear trailing arms for 6cyl ones, with rear 323i calipers and discs
But somewhere in here I am sure I 've seen people swapping from drums to discs and calipers, without replacing rear arms
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Re: rear DRUM to disc conversion?

Post by uwbuurman »

maybe but just a swap for 323i parts is the easiest way to go. Like you did.
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Re: rear DRUM to disc conversion?

Post by petroscf »

And then I guess you're almost ready to fit the 30 325i rear calipers as the next upgrade?
I am not sure how easy this would be with converted 4cyl rear arms-maybe somebody who has done this could help here
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Jeroen
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Re: rear DRUM to disc conversion?

Post by Jeroen »

May fit fine in both cases as the bracket you're fitting it on prolly is the same?
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pihlen
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Re: rear DRUM to disc conversion?

Post by pihlen »

Jeroen wrote:May fit fine in both cases as the bracket you're fitting it on prolly is the same?
I cannot find any info about the rear brake swap for drum cars. Can you possibly describe what the bracket(s) are and if I have to make them myself or if I can buy them somewhere? Is it Volvo calipers that is the way to go or try to find the 323i E21 disks? I´m aiming at putting on the Volvo brakes in the front so i guess it would be good to stick to Volvos for the rear as well (also cheaper/easier to find than the 323i brakes)?
Always thankful for y'alls knowledge and help! (So far I guess I´ll get more help then being able to help out my self..so far) :)

Stefan from Gothenburg, Sweden.
https://www.instagram.com/p/BDLw16AM6dC ... schteeffoh
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Jeroen
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Re: rear DRUM to disc conversion?

Post by Jeroen »

Just the metal of the trailing arms you bolt the calipers onto. And as described above, use E30 calipers as these usually are widely available and fit after only minor adjustments. Also see the topic in the Top Tech Topics: http://www.bmwe21.nl/forum/viewtopic.php?f=61&t=20181
Regards/groeten, Jeroen
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joe14
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Re: rear DRUM to disc conversion?

Post by joe14 »

I believe people have done it or at least intended to do it using some VW caliper that has the handbrake built in.

I don't know of any information as to how to do it but I'm sure it's out there..
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Re: rear DRUM to disc conversion?

Post by brockzila »

Asking the questions that you are I would say your only option would be to swap rear arms.

Yes you can convert the rear drums to discs. But it's not a weekend job. There is several parts to design and make to get the set up to work.

Have a look at Holden Commodore front calipers for a bolt on replacement also.
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Re: rear DRUM to disc conversion?

Post by Jason_323i »

drJim did a post

e21/e30 rear disks, golf mark 3 hand brake callipers then make a bracket to join them together simples.

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pihlen
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Re: rear DRUM to disc conversion?

Post by pihlen »

ok cool. so if i'd go for volvo 240 in the front and vw golf mk3 in the back, how would i get a good brake bias front/rear brakes? i mean i can use a bias adjuster knob but is there anything more than that? like brake line inner diameter or whatever? i guess the adjuster knob is only for fine tuning rather than drastically changing bias? thanks.
Always thankful for y'alls knowledge and help! (So far I guess I´ll get more help then being able to help out my self..so far) :)

Stefan from Gothenburg, Sweden.
https://www.instagram.com/p/BDLw16AM6dC ... schteeffoh
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Re: rear DRUM to disc conversion?

Post by mcjjordan »

Im thinking vw calipers is the way to go , unsure of what handbrake cable to use though
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