Jump to content

14th Annual SoCal Vintage BMW Meet 2021! “All couped up”

Registration is still open. Rally from NorCal is scheduled for Friday. Post your event photos.

SoCal Vintage is Here! 

Post your photos!

Diff Dilemma


Recommended Posts

So i came across a LSD and 5 speed tranny from an e21 that's for sale. I was curious what the thoughts are on putting this in the tii? I cant actually look at them since they are a plane/boat ride away . I dont have the full details as Im waiting on his email back but i believe its a 3:64 ratio. I can update this with the info as soon as i get it.

Let the discussion begin

Link to comment
Share on other sites

I doubt it is a 3.64 more likely a 3.90. I'm guessing they are both from a S package E21. I don't know how much time you spend on the freeway cruising so the addition of the OD 5th gear might not really make much difference in MPG, and unless you have some serious engine mods you are not going to run out of Revs in top gear with what you already have. I lived on Oahu and know how little time you can actually "cruise" at anything over 50 MPH.

I think the OD box and 3.9 is a great addition here on the mainland but not sure it's worth the effort in HI. That being said, putting the 3.9 diff with the LSD will liven up the performance and I think a LSD is one of the best things you can do to your '02.

I have had a 75% Alpina LSD in a 4.1 diff in my car since 1975 and I installed a OD 5 speed in 1981 out of a wrecked E21 with 1500 miles. I love them but I'm switching to a CR 5 speed and 3.45 diff and moving the the Alpina LSD to the new diff.

Link to comment
Share on other sites

Well thanks for the tips--I wont be island forever--three or so more years. If for some reason the car isn't on the road by then, i got other issue and someone very lucky will get a refreshed 02 on the island. My other concern is going off this guys word about the condition. I hope hes telling the truth about stuff but he did mention he pulled the stuff from a trashed car. I am not sure if he even drove the car with the tranny and diff in. I have an email out to him asking him more info and just waiting to hear back. What would a good price be for a lsd and a 5 speed tranmission?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...