Hey everyone!

I picked up an RX7 LSD for my Miata, not sure of the year but my guess is the FC non turbo.

I took it apart and put it back together according to the diagram I attached - I then popped the output shafts in. I can't physically turn them! If I try rotating one, the other one seems to barely rotate a degree in the opposite direction and locks.

I should be able to spin these by hand, correct? Any idea what could be causing this? Thanks for your help

 

It's not clear to me what you're saying. You put the output shafts into the differential carrier (shown in your photo #1) and were expecting to rotate them them while the carrier remained stationary? If so, than you shouldn't be able to rotate the side shafts while the carrier remains stationary. The carrier assembly should rotate as a unit. Applying enough resistance to the opposite side shaft will allow for some slippage. That's the principle of operation of an LSD.

You need to reassemble the differential while correctly setting the R&P backlash and side bearing preload. You need a dial indicator and 7-8 inch micrometer for these settings. If you're changing R&P gears to alter the final drive ratio, than you'll also need to correctly set the pinion depth. If any of these setting are not within spec, than you'll either get a very noisy differential, shortened differential lifespan or both. Suggest that you take it to a differential shop for proper reassembly.