What LSD for 325i

[addison05]

Hello everybody! I'm new to this forum and to E30's. I recently bought my first car, a 1988 325i. It has what the diff tag says is a 2.93 open diff. I'm trying to figure out what E30 LSD I should be looking for as a direct bolt in.

[wilholl]

Hello everybody! I'm new to this forum and to E30's. I recently bought my first car, a 1988 325i. It has what the diff tag says is a 2.93 open diff. I'm trying to figure out what E30 LSD I should be looking for as a direct bolt in.

So, if this is a 1988 e30 325 with a 2.93 open, then what you probably have is really a 325 non-letter, otherwise called a Super eta.
This has a 2.7liter engine eta motor not quite the same as the 2.5liter "i" motor.
These have good lower end torque and great gas mileage compared to their 325i cousin.

So, a 3.25LSD diff would be a good choice

[efficient]

seems like someone swapped your diff if your car is originally a I model. most people run 3.73 or 4.10 diffs with i motors.

[E30NJ]

3.25 isn't bad. 4.10 is arguably the best but are kinda pricey for a good one.

[digger]

4.1 is way too short with a standard 260

[mr2peak]

What kind of driving do you do?

[TRAK WDW]

I just installed a 3.73 LSD into my 325i... Definitely my favorite mod!

If you commute on the fwy quite a bit, look into a lower gearing like the 3.25 lsd.

And btw, I believe all of the E30 rear diffs are interchangeable to different e30's, so they should all directly bolt onto yours.

[jalopi]

Use this calculator to figure out what your before/after revs will be & choose your diff accordingly.

http://www.teammfactory.com/gearcalculator.php?kmh=0&tirewidth=195&tireprofile=55&wheelsize=15&tirediameter1=23.44&maxrpm1=7000&finaldrive1=2.93&gearratio1=3.83&gearratio2=2.20&gearratio3=1.4&gearratio4=1&gearratio5=0.81&gearratio6=0&trannytype=&tirewidth2=195&tireprofile2=55&wheelsize2=15&tirediameter2=23.44&maxrpm2=7000&finaldrive2=4.1&gearratioa=3.83&gearratiob=2.2&gearratioc=1.4&gearratiod=1&gearratioe=0.81&gearratiof=0&trannytype=&tranny=Calculate+Transmission+1+%26+2

If this is a daily leave it alone, no need for a LSD. 2.9 is a good starter diff & will keep things quiet driving on the highway.

Cruise @ 65 in 5th is 2100rpm with the 2.93, 2700rpm with the 3.73, 3000rpm with the 4.10

Aren't 3.25's expensive and hard to come by?

[addison05]

Well, my plan was as a daily but also a little drifter. The car is going race land coils sometime this month so I was looking for an lsd for sliding around when it's wet. Thanks for the input!

[panose30]

I have 3,91 lsd and i think is the best
4,10 is too short