NB sub-frame in NA
#21
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And I get that now, and thanks for your response. I just found out the hardway that the NA U-joint would not work. It wasn't listed in any of the threads I saved for this swap. Nor did the NA tie rods worked either, though luckily Rock Out has the MOOG ones priced CHEAP!. Now at least, people will have a thread to go to, listing those A-most parts for a swap!
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NA tie rod ends work just fine. The FUCA balljoint is longer to accommodate the deeper NB taper pocket, and the NB steering arm point on the spindle is lifted, but you can bolt the NA tie rod end to it. In fact, that's the preferred setup for lowered cars. I can't recall where I read this, but IIRC Bob Bundy did the math and said that an NB subframe/rack/spindle setup with 93LE/94R tie rod ends produced nearly zero bumpsteer all the way to full bump travel.
To swap an NB subframe into an NA, you need these parts and only these parts (and why you need them):
To swap an NB subframe into an NA, you need these parts and only these parts (and why you need them):
- NB subframe (this alters the FLCA pickup points and improves camber gain)
- NB steering rack, inner tie-rods, and mounting hardware (this is more reliable than the NA rack)
- NB lower steering column universal joint (required to attach NA shaft to NB rack)
- NB front upper control arms (or NA arms with NB balljoints) and NB-specific upper balljoint nuts (required to use NB spindles)
- NB front spindles (this reduces bumpsteer)
- NA 93LE tie rod ends (this further reduces bumpsteer, to effectively zero)
Last edited by Savington; 08-27-2018 at 01:10 PM.
#23
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NA tie rod ends work just fine. The FUCA balljoint is longer to accommodate the deeper NB taper pocket, and the NB steering arm point on the spindle is lifted, but you can bolt the NA tie rod end to it. In fact, that's the preferred setup for lowered cars. I can't recall where I read this, but IIRC Bob Bundy did the math and said that an NB subframe/rack/spindle setup with 93LE/94R tie rod ends produced nearly zero bumpsteer all the way to full bump travel.
To swap an NB subframe into an NA, you need these parts and only these parts (and why you need them):
To swap an NB subframe into an NA, you need these parts and only these parts (and why you need them):
- NB subframe (this alters the FLCA pickup points and improves camber gain)
- NB steering rack, inner tie-rod ends, and mounting hardware (this is more reliable than the NA rack)
- NB lower steering column universal joint (required to attach NA shaft to NB rack)
- NB front upper control arms (or NA arms with NB balljoints) and NB-specific upper balljoint nuts (required to use NB spindles)
- NB front spindles (this reduces bumpsteer)
- NA 93LE tie rod ends (this further reduces bumpsteer, to effectively zero)
I just got screwed last night on the U-joint to the steering shaft. For that part number: NC10-32-850 hooks it all up. I mean you posted it on your list, but I found out last night, as it wasn't listed anywhere else. Not here, not on M.Net or even the Grassroots Forum. It is in 2 out 3 now!
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I distinctly remember reading a post by you saying that you had measured the bumpsteer with that combo (NB subframe/spindles + NA LE tie rods) and it was ~1/16" from static ride height to full bump.
#32
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Hehe, I paid $10. Right price, right place at the right time. I spent more on the U-Joint ($40) and the steering rack bracket ($2 used, NLA by Mazda, I bought 2 of them!), than I did on the rack and subframe itself!
#33
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And the NA steering column intermediate shaft won't work on the NB U-joint... If one tries to buy part NC10-32-090D new, is NLA. You then have to buy NC10-32-100D and new that one is oer $350, but used is less than $40 for both, thank GOD!
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I believe that's false. I read that on M.net before I did Rover's swap, so I ordered the NB intermediate shaft too. It's identical to the NA one. I then skipped it when I ordered the swap parts for my current customer S1/ST4 build, and it worked just fine. NA column, NA intermediate shaft, NB lower universal, NB rack.
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I believe that's false. I read that on M.net before I did Rover's swap, so I ordered the NB intermediate shaft too. It's identical to the NA one. I then skipped it when I ordered the swap parts for my current customer S1/ST4 build, and it worked just fine. NA column, NA intermediate shaft, NB lower universal, NB rack.
#36
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https://www.miataturbo.net/suspensio...me-swap-62426/
Darn it, right here is spelled out that the NB steering IMS is needed. Gosh darn it.
Darn it, right here is spelled out that the NB steering IMS is needed. Gosh darn it.
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#38
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I may just be tired, which I am, and in no way I'm trying to argue, just confused, that's all!
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Yes, but it has nothing to do with an incorrect length as you alluded to. The length is correct, the spline diameter is just larger on the NB rack. You need the NB u-joint for the diameter, not the length.
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Should I unbolt the rack, plug the u-joint to the shaft, and bolt the rack back?
Sorry for all the stupid q's, but I'm at a loss here!