bmwe21.net forums

E30 M3 LSD conversion.

It took quite a long time- but here is the pics for the e30 diffrensial in e21.

I have no idea what i did 5 years ago here,but i sure did it all over again.
It was wrong with about 35-40mm...
Did it different this time- I will use original e30 mounting.
It will then be easier to get good bushings, and i can buy a Z3M cover with extra cooling later.

So this was started 5 years ago in a dark garage laying on the floor with a bad mig welder.


Not gooood

All off



Made a new stronger mount


One mount finished


Second finished


Sorry but not any pics of the diff fitted- I forgot
Next is to sandblast under the car before remounting all things in the rear.
The subframe and arms also need TLC with new paint and all.

So finally I'm going somewhere with this



Edit on pic.

Finally some new pics! Looking good

Nice upgrade and great plans. Apart from welding a different mount, how much work is required to make the E30 diff fit ie to propshaft, subframe, driveshafts and so on?

The upgrade requires the new mount on the car itself, weld in an e30 center into the e21 subframe and new shorter driveshafts. We have made a jig to the sub so the original propshaft fits correct.
The exhaust system also don't fit after this, it has to go under the subframe- there's no room between the tanks with the e30 center on.
You can do it a bit more easier than me as well.
The other ones I have done I used e21 mounting on the car like the double alpina.
Then you dont need to do all the welding that i did on the my car. This is the first one I'm fitting with original e30 diffcover with e30 mount. So its a new experience for me.

I can take pic of the subframe when I have blasted it.

OK thanks, just curious as that how much work goes in there, I'll leave mine stock! But for your S50 conversion you need to beef things up anyway!

The best thing ever- refitting all parts

Tomorrow I`ll get finished in the rear with everything beside the wheels I think.

Sub for e30lsd




I am now taking everything apart in the front again,its finished with exaust and everything.
Next thing is some paint and last touch on every thing I have built.
Then I am putting in an M20B20 to get it registrated before I againg refit the S50...

It have taken 6 years give or take,but finally I can see the end of it

It will probably NOT gonna be a totally show car the first two years,it was painted 19 years ago and it is not 100% any longer. I won`t redo it at this point.

Nice! Make sure to take enough pictures this time!

Jeroen wrote:Nice! Make sure to take enough pictures this time!

I guess I have to

Nice work there. More pics are good.

Could not wait





Water tank engine compartment- not finished..




Built transmission mounting

Nice work! You've learned a thing or two in the years in between haha!

can i have a go on your quad please?

nas80 wrote:can i have a go on your quad please?

Hehe. My 6 year daugthers
110ccm

Mostly finished in the rear today with fuel pump and all,only thing missing is speed sensor,shafts and end subframe bushings.
Probably making the bushings and shafts tomorrow. The sensor is ordered incl plug.




Subframe bushings.