Just a fyi swaping just the inputshaft is not easy. The whole transmission must be broken down to get it in or out, which means totally separating both shafts and removing lots of gears and hubs, ect.
So yeah don't do it unless you know what your doing or with someone who does.
Just a warning though =
I do not suggest anyone do this yet
The transmission currently is stuck in 4th. I'm not sure if it is because the input shaft is just a little off or the brass blocker ring is the wrong size. ( the transmission shop gave me the wrong kit but I made it work).
This is my first time rebuilding a transmission. My instructor said it could be that the ring just needs to be broken in a little so we will see if this will even work when I get the whole car together.
If it does not work it could just mean that I did a bad job so I'll take it to a transmission shop and see what can be done.
So unless your willing to pioneer it don't do it.
I understand your concern. If I were to use a non-mated transmission/bell and require the resulting transmission to be torn down, I would likely spring for a full rebuild at a qualified shop. I would probably pull apart the donor myself though as it would not need to go back together.
What do you think the odds are of getting the length of the Miata bell?
hard to read your tape in the shaft spacing pics. I take it they are both 2 and 5/8"ish? Don't want to be a PITA, but could you verify exact measurement please? Don't need both. Its quite obvious they are the same. Don't need a pic of it either. Measure center to center.
or get a manual rack like i had. my test fit was almost perfect because the manual rack didnt take up so much space.
also what oil pan are you using?
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