Miata gears in an SA transmission?
 

I'm wondering if anyone knows if it's possible to put a Miata gearset in an SA transmission? I've seen the threads about it for FB boxes, but couldn't find any references to an SA conversion.

Looking to update the transmission in my 1971 RX2 vintage road racer, but the rules make me stick with a Mazda transmission. Would rather not chop up the tunnel to fit the remote shifter in.

Thanks.

It should work fine, you replace the whole center section of the transmission with the Miata one, and use the bell housing and tail shaft from your transmission. The output shafts are the same on all versions so your SA tailshaft will fit just fine, when you are using an FB transmission it is possible to use the Miata shifter tower and get improved shifting since it has a better detent mechanism but you should be able to use the same shifter housing that you have now.

Rodger Mandeville's shop used to build those style Trans for my vintage racing competitors, and those were good boxes. ISC can build a box like that too. I tried building one myself several years ago, but it didn't turn out right; I didn't have the skills to make things line up perfectly. It was many years ago! sorry but I can't remember specifics for you. I am still vintage racing, now with an American G-Force gear box bolted onto an RX-3 bell housing.

What you asked can be done by a skilled Mazda gear box rebuilder.

You can't use a Miata center section in an SA trans.

SA and FB put the shift rods in a different place in the case, so the shift fingers are different as are ALL of the case sections (including bellhousing) since the shift rods run through all three case sections.

You could put the Miata bits in an early SA case but you will have to swap the gearshafts over. You have to disassemble the Miata trans anyway to get the input shaft out to cut its length down.

you mean you just cant cut it down with a cut off wheel and file the teeth?:lol::lol:

kidding.

Thanks for the info. It looks like it's a simple to do to the FB box & quite a bit harder with the SA.

yes thats how we did our miata internal transplant. the input shaft doesnt sit in the pilot bearing but just barely kissing the e-shaft. i had it for 10years until the input shaft finally separated from the tranny after years of abuse.