differential

i currently have an 85 300 na coupe, i was wandering if there was a way to tell if my car has lsd, or if its an open type diferential? if its open, is there a way i could swap a viscous out of a z32?

Put the car up on jack stands. Rotate one of the rear wheels forward with your hand. If the other wheel spins in the same direction, it's an LSD. If it rotates the opposite direction it's an open differential.

The Z31 used the R200 rear diff I think, so there should be a swap with either a non-turbo Z32 or one of the other vehicles that used the R200 (like the 240SX).

Go find some ice on the road and put one side of the car on the ice and one on the pavement. if the one on the ice spins and the car doesn't move then it has an open diff. if the car moves like normal and the wheels spin at the same speed its an lsd.

ok thanks guys, i'll try to check tomorrow an see.

only 87-89 turbo's came with LSD's from the factory, the 88SS came with a VLSD, the rest were CLSD's.

an easy way to tell without jacking anything up is, the rear cover on the LSD has cooling fins on it, the open diffs are smooth.

All Z31's used the R200 diff. Iif i remember correctly, it's a direct swap if you can find an 87-89 turbo diff (still an R200). Yours came with the open diff from the factory.

yes they are all R200's, but no it's not a direct swap. the companion flanges differed between years and models. he would have to find the correct companion flange for the driveshaft. the upside is the axles are the same i believe. at least the axle stubs anyway... i think the turbo's had 4 bolt flanges and the n/a's had 6 bolt flanges... the way they mate to the differential and the hubs are the same.

i'm new here and am trying to research on the differential plenum. unfortunately, i can't find the information i need about it. is it the same as the intake plenum? i need to know its function in the differential. i hope somebody can help me.