Well I bought a secondhand lsd in fd casing. Was told it was an aftermarket 2way.

Asked here and was told it was an oem TII diff. https://www.rx7club.com/drifting-226...aring-1020917/

Read on the net that they go weak after i while and ill be running autox and track so i want it to be tight..

So I stripped it and then it got confusing.. When i searched for parts on mazdatrix they didnt look the same..
Mine havent got the big gold thrust washer, The conical springs have tabs on them, There seems to be moore friction plates..

Mine:


One that looks identical. Even got the three philipsscrews.

 

looks much like the REA which is just a modified OEM LSD so you should be fine by using the thicker clutch packs listed on mazdatrix. but i would call them with measurements first to see if the dimensions match up on the LSD discs(keep in mind yours will likely be thinned out from abuse).

 

Do u know much lock to re-a should have? It doesnt look like its done much miles actually.
Can i measure it somehow without mounting it to the car?

 

i can't answer that, the factory spec is all i know and the only way you can test it is by torque at the wheels with it fully assembled. your only comparison would likely be about 25-50% more torque over factory spec in the FSM.

 

look at the center section. the t shaped part and the 2 casings that go around it. that'll tell you if it's a 1/1.5/or 2 way:

 

Yes its a 2way. and ill put it in the car and measure the breaktrough. Thanks for the help.