Will a manual transmission from an S5 N/A bolt right up to an S4 N/A? Are there any differences? My guess is it would work fine, but I wanted to double check.

it willbolt upjust fine and work just fine with no mods other then make sure you use the matching year shifter as they are slightly differnt. however also note that a t2 trans will need a diff flywheel and starter and drive shaft if going to t2 trans. now as for what is really differnt between a s5 and 4 na trans. there is a 5 pound counter weight on the tail shaft and the gearing is slightly differnt.

hope that helps.

Rear Transmission mounts are unique to each of the series. S4's are flat acros the bottom of the tranny; S5's are in a Y-Configuration

As banzai pointed out the case of the trannys is different. If you have the proper crossmember for each tranny then they are a direct bolt in. If you don't have the crossmember you'll need it.

Thanks!

I have an s5 tranny in my s4. It came with the crossmember still attached to it, the gear seems to be a bit different. But overall not much of a difference except for smoother shift and less heat build up.

I would like to point out that the S4 and S5 shifter are 100% interchangeable in the trannies (Turbo shifter will fit as well).

The shift knobs are not; an S5 knob will not fit an S4 stick and vice versa.

thats because the shifter threads are different (or their diameter)?

Thread Jack.



Would a new miata 6 speed fit???

Interesting question.

Some year I will have 1 in my car but for all intents and purposes it fits about the same way that a 350 Chev fits.

The mid section of a 5 speed Miata bolts right into a RX7 tranny as does a first gen RX7 mid section. First gen RX7 will give you some lower gearing but at the sacrifice of lower strength. The tranny from an S5 NA is the strongest FC3S NA tranny made.



And yes the shift knob thread is different, hence the reason for my saying they wouldn't interchange.

I am confused with your answer because I am totally clueless about tranny's. What do you mean Mid section??. And does a Chevy 350 fit an S5 N/A bolt pattern (am I using the right lingo?) So if a miata 5 spd fits right up to an S5 is the Miata 6 speed the same?? What are they putting in the RX-8?=(If not the same 6 speed then really not interested in hearing)

[quote name='jhammons01' date='May 25 2005, 04:14 PM']I am confused with your answer because I am totally clueless about tranny's. What do you mean Mid section??. And does a Chevy 350 fit an S5 N/A bolt pattern (am I using the right lingo?) So if a miata 5 spd fits right up to an S5 is the Miata 6 speed the same?? What are they putting in the RX-8?=(If not the same 6 speed then really not interested in hearing)


[/quote]



You sure are confused,

The transmission is a bunch of sections bolted together, if you remove the tail section and the bell housing (front section) you are left with a middle section, basically containing all the gears.

A chevy 350 fits NOTHING on an RX7, but if you custom build EVERYTHING there is physically enough room to put it in the engine bay.

A miata 5-speed does NOT "bolt" right up, but the MID-section is usable and the Miata 6-speed is completely different than the 5-speed.

I understand that the Miata & RX8 trannies are very similar but I cannot personally verify this.

[quote name='jhammons01' date='May 24 2005, 10:29 PM']Thread Jack.



Would a new miata 6 speed fit???


[/quote]



no the engine to trans bolt pattern is way different between the miata and the rotary. the rx8 trans will bolt up to the fc engine, however you still need to fab a trans mount

SSSEEEE!!!!! I profess to know nothing!!! As a matter of fact I work in the ultra high vacuum industry, I try to make nothing!!! And the closer I get to nothing the happier I am!! (a little vaccum industry humer, sorry for boring you)



I would like a 6 speed. I have an Auto Tranny and it sucks. I have been looking around but nothing as detailed as even this thread as I am just now making up my mind as to what to go after. Any of your tranny thoughts or opinions would be great.

unless you are looking to potentially pay a custom shop some big bucks, you should stick to an NA 5 speed for your conversion.

Once you get some more experience with these things, have a shop to work in and some good design/fabrication skills; then tackle the installation of a non-stock tranny.



PS I am not trying to imply you have non of these things, I am merely making a point. https://www.nopistons.com/forums/pub...IR#>/wacko.png https://www.nopistons.com/forums/pub...DIR#>/wink.png

I can do all this work, I completely rebuilt my motor here in my garage. I have the capablilties to do the work I just need direction as to what to get. I have never, never, never done any tranny work other than clutchs or swapping one for the other of the same time. This is the fisrt time on my 41 years I have wanted to do something a little custom to a tranny.



Oh and swapping a 2 spd hydroglide in a chevy is not "custom".

aftermarket s4 and s5 clutches are interchangeable?

only turbo and n/a are different.



if you look at part listings from ACT (since its so popular with us; i have an act clutch) they list separate parts for na and turbo but not different years. (says n/a from 83-91)