E-30 e differential Q's

["Rod Birch" <HOTROD930@xxxxxxxxxxxxx>]

My experience with my own 1986 325 (e style) is that my factory differential
was a 2.93 open rear end, and after receiving great advice from many
listmembers, I upgraded to the 3.25:1 LSD differential from a 535i and now
my car no longer has that "waiting period" when accelerating.  The freeway
speeds show about 300 rpm higher (I think), but the car still seems fine at
80 mph for long periods.  I understand that going with 3.73 gears from a
325i is just way too high for the 'e' low revving engine, even with a
performance chip.  My experience agrees with this.  I've heard about the
3.46 gears, harder to find, but probably a slight improvement in
acceleration over the 3.25 gears at a cost of slightly higher rpm (over
3.25) on the freeway.

Even with the K&N filter, modified airbox, exhaust, Jim C chip, etc., I
think that the differential swap was the best thing that I did, and I was
lucky enough to pick it up from a local guy for $200.

my $.02

- -Rod Birch