E23/24/28 Big Case Diff Ratios

[e30-323ti]

Hi Guys,
Just wanting to know if the internals from a E32/34 diff (Lots of ratios to choose from) will fit into the E23/24/28 case??
Big case that is, from the E28 M5,E24 M6 & E23 735i.
The ETK says that the LSD center is the same for all, but no clues about the crown & pinnion!?!?!

Thanks

[JamesM3M5]

There are probably more ratios for the standard E30/E28 diff case. Off the top of my head, I can think of:

2.73
2.93
3.07
3.25
3.46
3.64
3.73
3.91
4.10
4.45 (rare)
5.00 (ultra rare)

Those diffs handle well over 400BHP without flinching.

The big case fits the E34 V8 ratios. Standard in the US E28 M5 and E24 M6 was a 3.91. The Euro cars got a 3.73. E34 V8s had much lower ratios.

[e30-323ti]

Thanks for that James.

I have heard a few stories of the medium case diff's shitting themselves.
Mainly to do with the stub axles shearing the splines off, thats the E30 CV sized stub axles, but I have not heard anything on the E28 larger CV stub axles failing!?!?! Whats your experience.
I have heard that the E28 inner CV's can be fitted to the E30 axles, so the larger dia stub axles can be used???

As for the Big Case ratio's:
I have a diff from a E23 735i 3.25:1

Was interested in the E32 735i big case ratio's that are avaliable and weather they can be fitted to the E23 big case diff??
4.27
3.91
3.64
3.45

Of course there are more ratios from other models too.

[e30-323ti]

bump.

any more thoughts people.

[Brett Anderson]

Thanks for that James.

I have heard a few stories of the medium case diff's shitting themselves.
Mainly to do with the stub axles shearing the splines off, thats the E30 CV sized stub axles, but I have not heard anything on the E28 larger CV stub axles failing!?!?! Whats your experience.
I have heard that the E28 inner CV's can be fitted to the E30 axles, so the larger dia stub axles can be used???

As for the Big Case ratio's:
I have a diff from a E23 735i 3.25:1

Was interested in the E32 735i big case ratio's that are avaliable and weather they can be fitted to the E23 big case diff??
4.27
3.91
3.64
3.45

Of course there are more ratios from other models too.



All type 210 gear sets are interchangeable. Available ratios are:
3.15
3.23
3.25
3.45
3.62
3.64
3.73
3.91
4.10

There are no other ratios available that will fit this housing. There were some rare Motorsport ratios that are no longer available.

If your 735i is a US model, it does not have the large type 210 diff. I wonder if you're confusing medium and large with small and medium (type 168, type 188)

Brett Anderson

[e30-323ti]

Awesome, thanks Brett.

The diff is from a Euro E23 735i.

So just to get a definite, Yes:
I can pull the internals from a E32 735i Large case (3.91 type 210) diff and fit them to my E23 Large casee (3.25 type 210) diff.

by any chance does 168, 188 & 210 refer to the crown wheel diameter??

[e30-323ti]

bumpity bump

[e30-323ti]

Well I guess those that know don't frequent here that often??