So I have an 88 GXL and the LSD isn't locking the rear wheels. As I intend to drift this car, this is a problem. I'm really not too sure how to get ahold of a diff that locks. I initially thought about welding the differential, but I don't really want to do that and someone told me the LSD is a pain to weld. They told me that a NA Miata diff can fit in an FC pumpkin and you can just weld that. Does anybody know about this? More specifically does anyone know of this working without catastrophic failure? Or would I be better of trying to rebuild my LSD? I've been recently considering that it may just need new clutches. Gimme your opinions.

 

I do not have a lot of experience with diff interchange but in regards to your question - if you are going to weld the diff just put a open na (non lsd) differential assemble and weld that ( do not tear apart the lsd just to weld that). I would either take the time and money to rebuild the clutch style diff with thicker disc (can be obtained through mazdatrix) but I would not tear up the original lsd diff as they are hard to find for a n/a. I am actually in the same situation as I have a 86 gxl donor car that has a cultch style diff that I am going to swap into my 87 base after I rebuild the diff first, but also entertained welding my na open diff just to get me by until I can get the money together to rebuild the clutch style. Just keep in mind when you strengthen one part that the next weakest link in the system will be the one to break.

This is all just my opinion.

 

Thanks for the insight. I’ve really been considering rebuilding the diff because I just don’t like the idea of having a welded diff and I don’t know how sturdy the rest of the drive train is. However I’ve never taken apart a differential before so I’m not sure how difficult it is to rebuild.

 

Welded diffs are really clunky and a pain to drive on the street.