if the T57 has 11 to 46 teeth and a 35 has 14 to 54 . Has the 57 a much bigger modul or is the differential housing smaller compare to a 35 ? I think the 35 has Modul 4 .

Hi udo not sure I totaly understand the question or the term modul but T57 centre cases are 2 types early ones are as all 4bolt touring car cases essentally the same as a 35 but with an extra bolt on the torque arm flange.
The later ones are totally different they are ribbed and have a totally different type of fixing to the axel trumpet I have some photos at work I can upload on Monday.

how can it be , totally different type of fixing to the axel trumpet ?

Hi Udo, that is a late centre casing with the ribs, Trumpets to this will not fit the older style diff or vice versa, the late T57 and Brescia are two types that have less interchangability attched is a photo of an early T57 casing i beleve its essentaly the the same as all other 4 bolt touring cases.
Yours i beleve also has 9mm bolts?

It looks to me like a T35 casing . Is it maybe the same ?

So what is the chassis number of the car Udo?

Yep almost the same as a 35 but Torque arm flange is different this is a replica part but it shows a 4 bolt flange. It is upside down so to speek, when alterd to fit a GP it was common practive to remove bottom right corner making a 3 bolt ala GP?

does that make sence?

sorry , but I do not know the chassis number . I do not care so much about this numbers

#57481

Uwe , can you say what year ?

Oh - I thought it was your car. Not just one of the Schlumpf statues.

I think everybody knows this car .