FLanderos

i have a 87 fc. the tranny is stuck in neutral, and if it isn't a cheap fix then i'm going to replace the tranny altogether. my question is this: what will i benefit, if anything, by swapping in a t-56 six speed from a mustang, and is there any kits for such a swap. the tranny gears would be as follows:

1st-> 2.97
2nd-> 2.07
3rd-> 1.43
4th-> 1.00
5th-> 0.80
6th-> 0.62

final drive-> 4.30

thanks, any help would be great.

francisco.

Brismo7

iTrader: (2)

for your rotary?

Even though your not swapping the motor, i'm still afraid this will **** of the rotary gods...

Black91n/a

I've never seen any kit to do this. You'd need a custom bellhousing or some sort of adapter to mate the T56 with a rotary bellhousing, then you'd need a custom clutch, a custom flywheel, a custom transmission mount, maybe a custom shifter to put it in the right place, you'd need to figure out how to get all its sensors to work with the chassis, you'd need to figure out how to get the speedo to work, maybe a new throwout bearing, and so on. Not an easy task, not by a long shot.

I have seen an adapter for a T5 to a roatry bellhousing, but the rest is still up to you.

FLanderos

i know it would be no easy task, but what would be the benefit, if any, of such a possible swap?

That Rx-7 kid

^just to say you have one? I honestly dont kno haha thats a good question.

skatingsamurai

is there a way to just rebuild your current tranny to have new gearing and give it 6 gears? i have no idea if that is possible. but at least you would have a transmission that mates properly as well as the clutch. possibly. but thats just a thought, i really have no experience swapping or doing custom tranny work.

manslayerx9

the benefit would be 6 gears and a lower final drive and stronger than even an fd trans. but then you need to be making a lot of power to need a stronger trans in an fc but it would be a cool swap. for more info check in the 3rd gen section.

Sideways7

iTrader: (7)

Unless you have a T-56 laying around for free, then its not worth the swap. Even if you DO have one for free its probably not worth the swap. You would probably get a little better highway mileage, and a little better acceleration, but it would require a substantial amount of fabrication to make it work. You would probably spend a lot more money making it work than just fixing your existing tranny, and almost definitely spend more money than just getting an working tranny.
Also, I can't recall anyone breaking a tranny from too much power with an NA engine, so don't think it will really add much reliability.

FLanderos

well, i work at a mustang performance shop, so i have a few parts laying around. i want my fc because its different from all the 5.0s around here, but something that can keep up with all the supercharged 347s as well.

TitaniumTT

Nope, T-56 doesn't like to be shifted @ rotary RPM's anyway. Search in the 20B section as there are a few ideas floating around in there

If you don't know what the benefit is why are you even asking?

For certain applications there are benefits, I really doubt this is going to be such a case though

Quaiffe makes a dog gear 6-speed gear set for the turbo cases. It's $7,200 though

3rd gen section will laugh at you. 20B section.

QFT

Yeah, swapping a T-56 in isn't going to help your 120RWHP keep up with supercharged 347's

rowtareh?

iTrader: (1)

Is this an N/A or TII? If it's N/A, there is NO reason to do a swap like this. You can find a used N/A S4 transmission for cheap. I sold one with 75k miles on it with the clutch and flywheel for less than $100.00.

ajsuper7

A few years ago i read about a n/a fc that had a miata 6spd in it and it did not require all that much fab work but i do not recall the details on how they made it work. If i remeber correctly it was a shop that fit the miata gears and internals into a fc 5spd...but i may be way off my mind is getting fuzzy with age.

initial D is REAL!

quaiffe makes a semi helical tranny with synchros

Sideways7

iTrader: (7)

A couple people on here have done this as well. There is a full writeup in the archives. You swap the miata internals into the case from an FC, so its a fairly straightforward deal.

Black91n/a

That's for the 5 speed Miata gears though, as it's the same basic tranny. The 6 speed is totally different. You could use the RX-8 tranny if you really wanted to. It won't be quite bolt in, but easier than just about anything else non-RX-7 to start with.

Sideways7

iTrader: (7)

Oh, sorry didn't think about that.

As for the RX-8 tranny, its a total waste of time. Its not really any stronger than an NA tranny, and it basically has the same gear ratios. If I remember right it effectively has an extra gear stuck in between 2nd and 3rd or something like that. Theres a thread around with the details. Either way, it provides an extra, nearly useless shift and about the same (maybe ever shorter!) 6th gear as the FC 5th gear, so no better gas mileage.

TitaniumTT

KNOW WHAT YOU ARE TALKING ABOUT BEFORE YOU POST INACCURATE INFORMATION!!!! YOU COULDN'T BE MORE WRONG IF YOU TRIED!!!!!
THERE IS AN ACTUAL RULE FOR PEOPLE LIKE YOU!

pfsantos

iTrader: (1)

Last time I posted in red letters (and they were smaller and not underlined), some guy gave me attitude, and it wasn't for him, I was right and gave good advice.

The swap is not worth it, unless you like a challenge with no gain worth mentioning, except that you did it.

(grabs popcorn)

TitaniumTT

Now for the facts - AGAIN!
The RX8 trans bolts up to the 13B. That's where it ends -
You need to use a turbo flywheel and clutch
You need to make an adapter for the slave
You need a custom driveshaft
You need to build a custom trans mount
You need to use an electronic speedometer and adapt a hal-effect sensor
The shifter is 3.625" forward on the FE trans
There in an FD in the UK running 9's on this box in stock form - WEAK TRANS MY ***!!!!!!!!!
There is no "extra" gear thrown in as people like to say - STOP SAYING THERE IS AN EXTRA GEAR!!!! IT'S NOT THERE!!!! ALL THE GEARS WERE TIGHTENED!!!!!

Where's the extra gear??? Seriously where is this extra gear everyone is talking about. I see gear box's that look like this

---FE---
3.760
2.269 60%
1.645 72%
1.187 72%
1 84%
.843 84%

---FC---
3.483
2.015 58%
1.391 69%
1 71%
.719 72%

Graph & numerical - THEY DID NOT STICK IN A RANDOM ARBITRARY GEAR!!!!! THEY TIGHTED EVERY SINGLE SHIFT!!!! Could it be better? Yes, the FC trans has a better overdrive and will yeild better gas mileage. Personally I would like to see a .719 of the S5/6 trans or even better the .697 of the N/A's but that's just me. Remember, Mazda never expected anyone to put this trans in the FC so why would they design ratio's for it. Regardless, you're looking at a ~16% increase in revs, what does that transfer into gas mileage???

TitaniumTT

Why's the swap not worth it? Please tell me. If the swap isn't worth it why are there a ton (A TON) of full race P-Ports running around with this gearbox? Why am I planning on doing this swap?
For the average ricer who wants a cool 6-spd shift ****, no it's not worth it. But is has it's place for certain people.

Black91n/a

Hehehe, look what I started...

Anyway, yes, having closer spaced gears is a good thing. It gives you better acceleration by keeping you further up in the rev range, where you're making more power. Is it a direct bolt in? No, but it's a hell of a lot easier than something like a T56, that's for sure. At least parts of it bolt up, like you can get a clutch and flywheel off the shelf, there's no need to make a custom bellhousing or adapter. This will save you time and money. It is possible to move shifters around by modifying the transmission, I've seen it done, or you can use a bent lever or a linkage to move the **** back to the stock location.

If you were concerned that the shorter 6th compared to the RX-7 5th would cut down on your milage, then swap in a 3.9 ring and pinion gear to bring the revs down a bit. Personally, on my NA, I like having a shorter 5th (I'm using a hybrid FB/FC tranny now with a >.8 5th). It gives me more pulling power in 5th to go up hills, accelerate past people and so on without needing to downshift as much, where it felt quite gutless before with its much taller 5th. To me that makes for more relaxed cruising.

pfsantos

iTrader: (1)

Come on Titanium, chill a little.

Considering no future ambitions power-wise were mentioned, the swap doesn't make senser for him, unless he mentions otherwise. I never specifically said it's not worth it for *everyone*.

TitaniumTT

That is REALLY chill for me

Regardless, you said -
To me "the swap is not worth it," is exactely the same as saying "the swap is not worth it for anyone." You're stating fact that the swap is not worth it. Please don't backtrack.

I'm telling you there is a gain for some people. Black91 nailed it for most, others have done alot of math and know that they in certain turns, based on speed, driving style, whatever, they could use different or tighter ratios. For me it has to do with a pair of turbo's and keeping the RPM's above a certain point without boucing the damn thing off the rev-limiter every single time. For this particular n00b it seems like he feels that swapping in a T-56 will allow him to keep up with blown 347's. That's the way I read it.

Regardless, powerlevels are not the reason to swap out an FC TII trans for an FE trans. Although I would be very curious to see at what power level the FE trans' really start breaking. No one knows for sure.

MazdaMike02

iTrader: (4)

Question: Why do you feel compelled to absolutely destroy anybody who says anything wrong? Do you get any specific joy out of shutting down people younger that have less experience than you?

As far as the FE tranny I heard a few wrong things which Titanium proved otherwise, it looks like a great idea if you've got certain HP goals.
But as far as replacing your stock components with an FE tranny or a t-56..thats just stupid especially if this thing is daily driven or driven often. What I think you should do is, drop the tranny and make an attempt at rebuilding it..its really not that hard, its easier than an auto tranny. Anyways, if its not rebuildable go buy a used S4 tranny from the wreckers or from a member or whatever. And do the associated things when buying used.

pfsantos

iTrader: (1)

O.K. I could have explained myself better. What I meant is the swap will not help a bone stock S4 NA more for the average driver than the work involved. Is that better?