calling all diff guru please

[evilming 6n2]

hi there i want to have your opinion about a diff swap please.i have swap my 318 m40 auto to manual and the diff is a medium case open 4,10 do i need to swap it for another one?if yes what would be the good ratio to have?
i have found an medium 3,73 lsd diff from an e34 can i swap the parts in my current diff please
all help is welcome from you guys :bow::bow:

[MR 325]

No, you don't need to swap it! Just keep the 4.10 differential in there.

[frankie591]

swap it to an lsd if you want, but I'd definitely keep the 4.10 ratio with your motor.

[evilming 6n2]

thank you so much for your help and response so if i understand i can swap the e34 lsd internal and keep 4,10 ratio gear in my medium diff case?

[frankie591]

if they are both medium case differentials then you can just swap on the e30 cover and output flanges. much easier than swapping the internals over to an e30 medium case.