E36 legs on e21

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raseeda green
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E36 legs on e21

Post by raseeda green »

Hi all
I've heard of people changing e36 legs on to an e30 will this work aswell for e21
I want a brake upgrade and thought that if I upgrade then I could change the whole legs so as to have more choice on wheels and suspension. Please can you help.
Thank you


316 auto raseeda green
323 red m52 modified
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uwbuurman
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Re: E36 legs on e21

Post by uwbuurman »

On a e30 they put the rear hubs from an e36 compact, because thats a straigt fit. The compact has the old e30 rear axle, thats why. Then they fit e36 front legs, with e30 springs (e36 are to round) and e36 m3 3.2 swingarms. In that way you have 5x120 instead of 4x108 This all will not fit straigt onto the e21.
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raseeda green
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Re: E36 legs on e21

Post by raseeda green »

There is a read up of e28 and e12 hubs to fit the e21 so I may go to this route thank you man
316 auto raseeda green
323 red m52 modified
ruh
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Re: E36 legs on e21

Post by ruh »

I have the E28 / E12 setup on my car. It is alot of work , and you need to sacrifice the old E21 rear beam.

You need the E28 rear axle and beams and change the cross rear beam to the E21. It will then bolt straight up. You need to be aware though that the E28 rear axle has a wider track by about 1" (3cm) in each side. You can use E39 coilovers for the rear when done.

Frontwise the E12 hubs bolts directly up on any E21 front strut but the 4 piston E12 brake calipers will only fit on E21 323 struts. So you need to do some more welding, or get some 323 struts.

On a scale from 1-10 where 10 is rebuilding a complete engine i will score this an 8. You really need to know what you are doing with the welder to get that e28 rear axle set up properly. Fender flares is a must (or high offset wheels).

Here´s a pic of my ride with 5 lugs.

Image

The wheels are 8x15 ET0 Trans Am Turbo wheels with 205 Kumho Ecsta Semislicks.

Cheers
RUH
With best regards
RUH
brockzila
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Re: E36 legs on e21

Post by brockzila »

ruh wrote:I have the E28 / E12 setup on my car. It is alot of work , and you need to sacrifice the old E21 rear beam.

You need the E28 rear axle and beams and change the cross rear beam to the E21. It will then bolt straight up. You need to be aware though that the E28 rear axle has a wider track by about 1" (3cm) in each side. You can use E39 coilovers for the rear when done.

Frontwise the E12 hubs bolts directly up on any E21 front strut but the 4 piston E12 brake calipers will only fit on E21 323 struts. So you need to do some more welding, or get some 323 struts.

On a scale from 1-10 where 10 is rebuilding a complete engine i will score this an 8. You really need to know what you are doing with the welder to get that e28 rear axle set up properly. Fender flares is a must (or high offset wheels).

Here´s a pic of my ride with 5 lugs.

Image

The wheels are 8x15 ET0 Trans Am Turbo wheels with 205 Kumho Ecsta Semislicks.

Cheers
RUH

Hi I have the complete e28 rear end with a mid case lsd almost ready to start making jigs and tmocking up the conversion.

What have you used for the rear swaybar??

I have seen guys use custom as I havebeen told the e28 bar interfears with the boot/tyre well.

What are your flairs off. My image for my car is very close to yours .Looks good.
ruh
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Re: E36 legs on e21

Post by ruh »

brockzila wrote: Hi I have the complete e28 rear end with a mid case lsd almost ready to start making jigs and tmocking up the conversion.

What have you used for the rear swaybar??

I have seen guys use custom as I havebeen told the e28 bar interfears with the boot/tyre well.

What are your flairs off. My image for my car is very close to yours .Looks good.
Cheers mate, i have no rear sway bar. I am not using it as the suspension is very VERY firm - from a M5 E39 (1700kg vs my 900kg). That also ensures full traction all the time, and in extreme situations you will get a front wheel lift when cornering etc. e_surprised

It is very hard to get everything lined up correctly so my advise is to just go ahead slow and measure everything twice or trice to make sure everything sits exactly where it´s meant to be.

My flares are made of some soft rubber/plastic stuff, i think i bought them in Estonia on Ebay.uk. They are 120mm in size but only gives around 6 cm of extra clearance. In my case that was just enough.
With best regards
RUH
brockzila
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Re: E36 legs on e21

Post by brockzila »

Thanks man.

That's good to know. I will be in touch for more info closer to the time .

Oh also what did you do with the drive shaft .
ruh
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Re: E36 legs on e21

Post by ruh »

brockzila wrote:Thanks man.

That's good to know. I will be in touch for more info closer to the time .

Oh also what did you do with the drive shaft .
The drive shaft is plug´n play, so no worries there.

You will need to remove an exhaust hanger and you will need to cut out a bit in the spare wheel well.

This pic is from when i was mocking the hole thing up.

Image[/URL][/img]

Also i can mention that E34 polyurethane bushings will fit the E29 sway arms :crazy

Image

Image
With best regards
RUH
brockzila
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Re: E36 legs on e21

Post by brockzila »

I'm going to start a new thread so we can continue this exchange of knowledge.
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raseeda green
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Re: E36 legs on e21

Post by raseeda green »

Cheers for the info. I think I'm stay to a more simpler set up.
316 auto raseeda green
323 red m52 modified
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