at the beginning... Subframe and differential...

As I mentioned before the first cassis was very rusty I would say "sieve". :) So I`ve just swapped for another one. First one was a black one the new base is a blue one. That`s why you can see on some pictures black and on others blue E21 body. By the first plan I wanted to install and use an E30 (E34) small or medium case diff. Why? You have more chance of finding an E30 LSD then an E21 LSD. (I also have to mention the big difference between the price and the ratio range.) I found unsolvable of putting the E30 diff into an E21 subframe. It just wasn`t. :) That was the first lesson if you really want something YOU CAN DO IT! We had cut off the midde part of an E30 and an E21 subframe and we just welded the E30 frame into an E21. :) Voila! It`s done:

 

As the E30 diff wider than E21 diff I had to reduce the length of the half axles by 15mm. It was the first plan and plans have always been changing. :) This modification above happened in ~ 2005 and I just changed my mind lately. :) Why again?? :) Because E30 small and large case diffs are just also not strong enough (TYP 168 and TYP 188). So Im selling my small case E30 non-LSD diff with 3.38 ratio. As I discovered on forums there are couple of diffs which have 210 large case and also just simple bolt on E30 (E34) subframe. This one: 

 

This diff case is from BMW E23. Part no: 33111210410 (but there are some other big 210 diffs which fit to E30 subframe too) (Pictures from Powerfanatics.com)

This large case 33111210410 differential is available in: 

E23 733i Saloon, USA 

E23 735i Saloon, USA 

E23 728i Saloon, Europe 

E23 728iS Saloon, Europe 

E23 732i Saloon, Europe  

E24 633CSi Coupé, USA 

E24 635CSi Coupé, USA 

E24 628CSi Coupé, Europe 

E24 635CSi Coupé, Europe  

E28 524td Saloon, USA 

E28 528e Saloon, USA 

E28 533i Saloon, USA 

E28 535i Saloon, USA 

E28 518 Saloon, Europe 

E28 518i Saloon, Europe 

E28 520i Saloon, Europe 

E28 524d Saloon, Europe 

E28 524td Saloon, Europe 

E28 525e Saloon, Europe 

E28 525i Saloon, Europe 

E28 528i Saloon, Europe 

E28 535i Saloon, Europe 

E28 M535i Saloon, Europe

It does fit to E30 subframe and also has large case. How will you know it is a medium or big case differential if you are not an expert? Big TYP 210 diffs have 8 bolts for the side bearing seals.

Well I just couldnt find 210 big case differental which fits to E30 subframe therefore I`ve bought my new diff which came off an E36 M3 EVO 3.2. The greatest thing in this diff is the ratio. Just that I wanted to get. 3.23 and LSD. :) This ratio satisfies me. Under this ratio it would`ve been too long or over this ratio probably I would`ve have found it too short. Now I just have to find an E46 320d 6 speed (GS6 37DZ) gearbox. This gearbox has this ratio:

I 5.14
II 2.83
III 1.79
IV 1.26
V 1.00
VI 0.83 

This gearbox`s bell also wont fit to M20 engine. :) but... no worries mate! :)

Of course this E36 M3 diff wont fit onto my modified E30 subframe eighter because this M3 diff housing is different. Just to make me happy. :( So... probably I wont be able use my E21-E30 hybrid subframe that I had modified. Instead I have to modify my spare E21 subframe. But that story will be continued in next summer. And some pictures of my new TYP 210 big case E36 M3 EVO diff was bought for 170 quid:

(Well.. when I brought it home my wife just shouted at me "What a f..ck is this piece of oily metal shit doing on my corridor??" Lack of respect for BMW! Shame on her!)

Im planning to modify the closing ratio of this diff from 20% to 40%. But this modification will cost another £150.