e30 rear diff question

[joecoolinatl]

what were all the diff's that came with the 2.7 and 2.5 e30s?
and were some model specific? i.e. ive always heard that the diff on the autos was 4.10 but when i looked at my daily drivers today ( 87 eta auto) it is a 2.93 (open) , ive only had this one since august, did a previous owner change it out?
and
if it did go from a 4.10 to a 2.93
what are the pros/cons?
thanks

[Rigmaster]

Re: e30 rear diff question

what were all the diff's that came with the 2.7 and 2.5 e30s?
and were some model specific? i.e. ive always heard that the diff on the autos was 4.10 but when i looked at my daily drivers today ( 87 eta auto) it is a 2.93 (open) , ive only had this one since august, did a previous owner change it out?
and
if it did go from a 4.10 to a 2.93
what are the pros/cons?
thanks

Here's a quick rundown- off the top of my head.

325/325e/325es have either a 2.79 (early cars- like 84-85) or a 2.93 (86-up) regardless of 5 speed or auto- most 325es' had 293 LSD, LSD was optional on others

325i/325is ALL 5 speed cars had 3.73, Auto had 3.73 for 87+88, auto had 410 89-up. All 325is' had LSD, optional on other cars- seem to be alot of LSD's on later cars with leather interior- but it's not 100%.

You would not want a 410 in your eta, a 3.25 ratio would be a good upgrade, you can go with a higher number, but I would ask around first for other's opinions. I've heard some eta owners who run a 3.73 and love it, and others who tried it and hated it.

Bret.

[BahnE30]

if your not on the highway very often a 3.73 is fun around town but on the high the old eta screams, with a 2.93 it runs 2000rpm at 60mph i'm guessing a 3.73 would put the rpms around 27-2800