The subframe is identical to an S14 in setup but I was having trouble tracking down if it would fit. The track width difference between the s14 and j30 is near an inch (25.4mm). The track width difference between the s13 and s14 is 10mm and there are quite a few options for offset bushings to make it fit. Well known stuff.
I had messaged someone in texas who had said he put the J30 subframe in his S14. I asked him if he had to stretch the bushings or anything, but he said it bolted in with no tricks. I had hope!
But the service manual dimensions kept telling me that was wrong and my own measurements backed up the service manuals. I was at the local pick and pull and found an S14 with the subframe still in it. Impatient to wait for my full teardown of the S13, which would have been when I would have put the subframe up in the car to verify my assumptions. Plus if the J30 and S14 were truly identical, I could resell one and make my money back!
But alas, the subframes are indeed an inch different. Since nobody has ever posted a picture, I took it upon myself to post up one:
These are the rearward bushings. As you can see, there is a full inch difference when you line one side up.
