Hey my coworker has a Miata with a 6 speed. I wonder can i swap this trans into my Fc3s? anyone know if it can handle the power?

Before you ask that question. You should ask yourself...



Can you weld?

What tolerance can you machine things to?

How good are you at doing sheet metal work?

How about general fabrication skills?



Things you would need to do.

-Custom made bell housing

-Custom fab a transmission cross memeber

-Design a new driveshaft

-Design a new linkage system if it's too far back or forward of the opening for the tranny tunnel



All those are important... UNLESS.... you have money. Then all is good.

Supposedly that tranny was designed to handle 300hp.

The above list by Cheers would be worst case scenario.

This is something I want to do someday, but I have never looked into it any further than "I want to do it someday"

the miata 6 speed is teh same as the rx8 6 speed I hear. It doesn't like torque. So 300 hp seems optimistic, unless it was 300 hp and 190 ft-lbs of torque.

Similarly; I understand that the NA tranny centersection is interchangeable on the Miata, FC and FD (the section containing the actual gears), although the gear ratios and design varies slightly they bolt up and work.

i would do a supra 6 speed swap before i would ever do a miata trans swap. or how about the rx-8 trans, atleast the bell housing is correct.

[quote name='DareBee' date='Jul 26 2005, 04:05 PM']Similarly; I understand that the NA tranny centersection is interchangeable on the Miata, FC and FD (the section containing the actual gears), although the gear ratios and design varies slightly they bolt up and work.


[/quote]





No.



The M series transmissions are the smoothcase models found in the fb, fc n/a, B2000/2200, and the 5 speed miatas. The internals are interchangable between those, and those only. The early ribcase trannies, fc TII, FD, and B2600 trannies are all from the R series, and are all interchangable within that series. The early ribcase trannies have the input shaft splines that match the later M series trannies, while the fc TII, FD, and B2600 all have a larger input shaft.



The miata 6 speed is an entirely new series of tranny, although with the rx8, it is now available with a bellhousing that bolts to a rotary, and uses the same diameter flywheel and input shaft size/spline as the fc TII and FD.

[quote name='mazdaspeed7' date='Jul 26 2005, 04:42 PM']The early ribcase trannies, fc TII, FD, and B2600 trannies are all from the R series, and are all interchangable within that series. The early ribcase trannies have the input shaft splines that match the later M series trannies, while the fc TII, FD, and B2600 all have a larger input shaft.


[/quote]

So the ribcased N/A trannies are the R series? https://www.nopistons.com/forums/pub...1047683561.gif



What are the gear ratios on the B2600?

[quote name='mazdaspeed7' date='Jul 26 2005, 05:42 PM']No.



The M series transmissions are the smoothcase models found in the fb, fc n/a, B2000/2200, and the 5 speed miatas. The internals are interchangable between those, and those only.


[/quote]



Isn't that what I said? (with exception to the B series part)

88TII 5th gear is higher than 89TII 5th gear??? I thought they were the same, with the only exception of the japanese domestic market TII trannies having a very high 5th gear.

[quote name='DareBee' date='Jul 27 2005, 07:40 AM']Isn't that what I said? (with exception to the B series part)


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No. There are 2 different series of transmissions in fc's that are not interchangable between them. The M series is in the 1st gens, n/a rx7, miata 5 speed and a few other. The R series, which will NOT drop into an M series case, wsa found in the fc TII and FD and others.





Cheers, the top gear is definately different between S4 and S5 TII trans.

interesting to note that the new miata had a new mazda designed 6 speed, not the one thats in the older miata/rx8.



speaking of the older 6 speed, ive never seen one fail, and they actually seem to shift ok once its broken in. granted our customers arent hot rodding anything though

[quote name='mazdaspeed7' date='Jul 27 2005, 09:56 AM']The M series is in the 1st gens, n/a rx7, miata 5 speed and a few other.
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That is exactly what I was thinking when I typed my first post; upon re-reading I realize that I accidentally typed FD where I had MEANT to type FB - sorry for the confusion. I also did NOT specify NA ONLY. https://www.nopistons.com/forums/pub...1047683664.gif



Also - someone was telling me the other day that the 79 - 80 FB had a different tranny altogether, I cannot confirm this 1 way or the other. Maybe someone else has input for this.

[quote name='DareBee' date='Jul 27 2005, 12:17 PM']That is exactly what I was thinking when I typed my first post; upon re-reading I realize that I accidentally typed FD where I had MEANT to type FB - sorry for the confusion. I also did NOT specify NA ONLY. https://www.nopistons.com/forums/pub...1047683664.gif



Also - someone was telling me the other day that the 79 - 80 FB had a different tranny altogether, I cannot confirm this 1 way or the other. Maybe someone else has input for this.


[/quote]





Not really true. Its still the M series, but its weaker than the later ones. I believe the M series trans were strengthened for 81 and again with the S5 fc n/a. Not sure, but possibly again for the miata, because Ive heard that the miata 5 speeds are stronger than fc n/a.

So there are no alternatives to the TII tranny? 6 gears would be nice https://www.nopistons.com/forums/pub...IR#>/smile.png

[quote name='SidewaysFC' date='Jul 27 2005, 01:44 PM']So there are no alternatives to the TII tranny? 6 gears would be nice https://www.nopistons.com/forums/pub...IR#>/smile.png


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The TII trans is the strongest trans you can have without major fabrication. The next step would be a T56 or a supra trans.

Fitting different gearboxes is very possible - the kit car guys over here use the RWD Ford gearboxes with a host of other engines - all you need to do is find the right combination of flywheel, clutch thrust bearing etc. which is not easy but maybe someone else has done it already and done the hard part for you. You might not need a new bellhousing either, you could make up an adapter plate to sit between the engine/gearbox.



As far as whether the box will take the power, well it's torque that you need to worry about, I don't know what torque the mx-5 engines make compared to the rotary, but I can't imagine they're worlds apart. Our Nissan makes nearly the same power as the bike-engine in my car, but if you somehow could hook it up to the bike's cd sized clutch I'd doubt it'd last too long.



Mark

from what i have learned the miata 5-spd transmissions will have the same bell housing and will bolt up, however you still need a custom driveshaft and i'm not quite sure if the shifter location will be wrong.



a modification that people DO perform is to swap in the gears from the 5-spd into an FC transmission, since the miata tranny has shorter ratios.



a little interesting fact: the S5 reverse gear has syncromesh, the S4 does not.

[quote name='mazdaspeed7' date='Jul 27 2005, 01:39 PM']The TII trans is the strongest trans you can have without major fabrication. The next step would be a T56 or a supra trans.


[/quote]



Viper https://www.nopistons.com/forums/pub...IR#>/boink.gif

He said the NEXT step. Isn't the viper tranny a heavily upgraded T56?

[quote name='coldfire' date='Jul 28 2005, 11:29 AM']from what i have learned the miata 5-spd transmissions will have the same bell housing and will bolt up, however you still need a custom driveshaft and i'm not quite sure if the shifter location will be wrong.



a modification that people DO perform is to swap in the gears from the 5-spd into an FC transmission, since the miata tranny has shorter ratios.



a little interesting fact: the S5 reverse gear has syncromesh, the S4 does not.


[/quote]



the miata bellhousing bolt pattern is totally different from the rotary. its easy to swap them however.

[quote name='SidewaysFC' date='Jul 28 2005, 06:09 PM']He said the NEXT step. Isn't the viper tranny a heavily upgraded T56?


[/quote]



It is an upgraded T56, but I dont know if I would go so far as to say heavily.

I know its good for 600ft lbs of torque! More than good enough https://www.nopistons.com/forums/pub...IR#>/smile.png

[quote name='1Revvin7' date='Jul 28 2005, 07:47 PM']I know its good for 600ft lbs of torque! More than good enough https://www.nopistons.com/forums/pub...IR#>/smile.png


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Haha. Easily!

r5md was my tranny on my b2600i if i remember correctly.. had i known i could just stick the damn t2 engine on the front with the proper bell housing i would have kept that mofo..

so really an RX-8 trans could or could not work? And is it true i heard that the Rx8 trans is a reworked miata one?

[quote name='Red Suns' date='Aug 2 2005, 05:41 PM']so really an RX-8 trans could or could not work? And is it true i heard that the Rx8 trans is a reworked miata one?


[/quote]



the rx8 trans is the same as the miata, just a different bellhousing to fit the rotary