5sp Transmission Upgrade ?

[ModMX3 - (Carmaster2005)]

I have Searched through many listings not to fine what im looking for. I have a 94 1.6L 5sp Transmission I want to know If there are any other swapable 5sp transmissions that will bolt up ? somthing with a higher final drive or 5th gear ? This would help a great deal .

[umcamara]

You have an F-series transmission. The GS model, as well as the BP Protege, Escort Gt and LX-E, and Kia Sephia have the G-series tranny. It has a shorter 1st, 2nd, and 3rd gear for faster acceleration if you have enough engien power, and a longer 4th, 5th, and final drive gear ratio.

I believe this would cause the engine to be turning slower at highway speeds in 4th and 5th gear.

I'm not positive, but as long as you change your drive shaft to the one from the G-series tranny, I think it's a relativley easy swap. Hope this helps.

If you look at the specs for the '95 MX-3 off the main page, it shows you all the gear ratios for the 2 different models.

[cyclonekid78]

The GS came with a K series tranny.

The G-series has a overall lower gear ratio then the F series. What I have seen done is swapping the G in and the using the 5th gear from the F series.
But the F-series has the highest 5th gear. As far as swappable trannys goes.

[umcamara]

If you look at the online shop manual it lists an F-series tranny for '95 4 cyl. and a G-series tranny for the '95 V6. Maybe I'm missing something here but I believe it's the V6 engine that's a K-series, whereas the 4 cyl. are B-series.

[Ryan]

Reviving an older thread!

concerning 4cyls, may they be SOHC or DOHC or BP, the only tranny options are F and G?
F is better mileage, the G better accleration. The F fifth gear can be swapped into the G for the same highway mileage?

Sorry, I don't understand trannies at all. Whats a final drive gear ratio? and how does one make gears 'taller'?

Do the V6's use a G series tranny? Are the V6 and 4cyl trannies interchangable?

[Nd4SpdSe]

The series is about the gears inside. but the casing differs. You can swap the gears from a G-series I4 into a g-series V6 and visa-versa cause they're all g-series gears, but you need the 4cyl g-series tranny case itself if you want to bolt it up to an 4cyl motor.

[wytbishop]

To answer your question about final drive...

Each "gear" (you're not actually selecting a gear when you put the tranny in "gear", you are selecting a pair of gears...you are selecting a gear ratio) in the tranny is actually a pair of gears. One on the input shaft and one on the output shaft. The input shaft spins at engine rpm. The output shaft rotational speed is determined by the gear ratio of the gear set that is selected. First "gear" which is short, has a small input gear and a large output gear so the output shaft is spinning much slower than the input shaft. The fifth "gear" pair of gears are closer in size so that the output shaft is spinning at almost the same rpm as the input shaft when in fifth.

The crankshaft turns the transmission input shaft (when the clutch is engaged) which has the input half of each gear set splined to it. When a "gear" is selected by the shift lever, that input gear is mated to its corresponding output gear. The output gear in turn spins the output shaft. The output shaft is mated to the ring gear of the differential and the differential of course has the drive shafts inserted into the spider gears. The ratio of the ring gear to the spider gears is the "Final Drive" ratio and it is constant. It can only be changed by changing the differential. In a 4.11 diff, the spider gear (and in turn the wheel) spins 1 revolution for every 4.105 (they round to the second decimal) revolutions of the ring gear. Our tranny is a 4.11 tranny and so is the Probe GT. Others are 3.89 (actually 3.885).

The individual gears of the different G-series trannies can be interchanged. However a 4.11 diff will not mate properly with a 3.89 output shaft. If you had a tranny with a 3.89 diff and wanted to do the MSP LSD install you would just take the output shaft from a 4.11 tranny and it would swap right in turning your tranny into a 4.11 tranny.

Hope that helps.

[Nd4SpdSe]

That pretty much sums it up, I made a post explaining that a few months ago, I'll quote that below.

Just 2 things
- Changing the gears other than 5th gear on the shafts I've been told is very difficult.
- Trying to put a mis-matched differential from the pinion gear won't work, because their phyisical size will differ. The pinion gear on the 4.38:1 would be physically smaller than the ones on the 4.11:1, and the ring gear around the differential is larger a 4.38:1 compared to the ring gear on a 4.11:1 differential. Because you can't change the distance between the output shaft and the differential, it won't work. I may "kinda" work if they're close enough, but i'd be affraid of it doing something funky in there and breaking something.


Here's my explanation on the final drive

No, not at all. The final drive is the gearing that multiplies your torque, leverage. The Mx-3/Probe and Mx-6/626 tranny's gears themselves are all the same, the final drive actually changes the (final drive) ratio of all the rears. (the 626/mx6 tranny uses a longer 5th gear over the Mx-6 tranny)

In front-wheel drive, it's a weird concept to understand what final drive is because FWD cars use all-in-one 'transaxle' system, but if you break it down using a rear-wheel drive system of a transmission + drive shaft + rear differential, it's easier to understand.

In explaining this, imagine an Mx-3 and a Mx-6, but say they're rear-wheel drive. They would both actually have the exact same transmission, so all the gears from 1 through 5 (and reverse) would all be the same (just ignoring the Mx-6 5th gear for this).

1st: 3.31
2nd: 1.83
3rd: 1.31
4th: 1.03
5th: 0.80

From that point on, this is where it differs. The final drive would be determined in the rear differential in the rear axle. If you ever hear anyone with a RWD car talking about them changing the gearing on the rear end, this is it. This basically changes the the length of all the gears without touching the transmission itself. On a RWD car, a final drive of 4.38:1 would mean that the drive shaft actually turns 4.38 times for every 1 turn of the axles/wheels. For 4.11:1, well, I'm sure you can figure that out. By having a larger number for the final drive, you bring the gears closer together (shorter), so theoretically improving acceleration, but having a lower top speed. If you have a smaller number for the final drive, the gears become longer, sacrificing acceleration for top speed.


Here's a basic break down for a FWD drive system


In red those would be your actual gears, 1st through 5th and reverse.

In green is where your final drive is determined; the small pinion gear and the ring gear around the differential. When it comes to the final drive in FWD cars, for the Mx-3/Probe, the pinion gear turns 4.38 times to make the differential turn once. In the Mx-6/626, it takes less turns, 4.11 turns of the pinion gear to make the differential turn once. A RWD car uses pinion gear & differential ring gear system as well, it just sits external to the tranny, in the rear differential, but function is basically identical FWD or RWD.

Now, in reference to the pinion gear and differential and how it determines the difference between the 4.38 and 4.11 trannys, it affects your LSD options. One of the options is to use the LSD from a MazdaSpeed Protege, but it's ring gear is matched for a 4.11:1 ratio pinion gear, so you'd have use an mx-6/626 tranny with 4:11:1 gears, swap the pinion gear from a 4:11:1 tranny into your Mx-3 tranny (if that's possible), or use the ring gear from the stock Mx-3 (4.38:1) differential and put it on the MSP LSD. There's also the Quaife LSD, it's pricey no doubt, but you need to use the ring year form what ever tranny your using.

[Ryan]

Okay... I did some research and pretty well understand the concepts and the physical workings...
what is the name of the final output gear? the biggest one in the box of the tranny? I understand changing it wouldn't work because it would be a physically different size, and would not mate properly.

The 'final drive' is the last (set?) of gears before axles? They never change. correct? this is within the dif?

since we are FWD, we use the 'transaxle' system. this is attached, not part of the tranny. I should just go look what my axles plug into, because I bet thats it. Is the 'final drive' within this system? This is our 'differential'?

The tranny and the diff need to match, which you guys outlined. Personally I don't care about LSD, so I wont concern myself with it.

I think i get it.

One could swap out the 5th gear for a lower engine speed at highway cruising speeds (and top speed, I guess) as well as a diff with a... lower gearing ratio? to add to the effect?

Just talking to myself, helps me understand, but I'm gonna click the submit button anyway so you can correct me if I'm wrong.

Oh, and what is the lowest engine speed for highway cruising we can possibly acheive and what do we need to change? from what? for v6 and the 4cyls?

[Nd4SpdSe]

You do understand the concept, your really close.

Okay... I did some research and pretty well understand the concepts and the physical workings...
what is the name of the final output gear? the biggest one in the box of the tranny? I understand changing it wouldn't work because it would be a physically different size, and would not mate properly.

The 'final drive' is the last (set?) of gears before axles? They never change. correct? this is within the dif?

since we are FWD, we use the 'transaxle' system. this is attached, not part of the tranny. I should just go look what my axles plug into, because I bet thats it. Is the 'final drive' within this system? This is our 'differential'?

The tranny and the diff need to match, which you guys outlined. Personally I don't care about LSD, so I wont concern myself with it.

The final output gear is the pinion gear, it drives the differential. The differential has a gear around it call the ring gear, since it's literally a ring with teeth, that's attached around the differential, turning the differential into a gear itself (that in turn, turns the cv shafts, etc). The pinion gear sits on the secondary/output shaft.

You need to match the the pinion gear with it's matching ring (differential) gear. Here's why:



You can change one gear, but the problem is that one is slightly smaller/larger (in this example there's a larger "ring gear"). Although the teeth may fit and overlap, it's still not right and may see issues either right away or in the long run. You can see the first pair match perfect. The second (lower) pair, there is a gap. One thing that would be done is to move them closer, but you can't, their distance is fixed in the tranny, so you have 2 choices, you make the pinion gear smaller, or the ring gear bigger. That's why you need the matching pinion gear and ring gear, cause all the same series trannies have all the same internal distances between the gears, so they'll match exactly as you need them to.


The transaxle, for a FWD car, basically it IS the tranny, it's the whole thing.

On a RWD car, the tranny is just that, just the gears. Than you have the driveshaft, the rear differential than the rear axles. In a FWD car, that's all-in-one, why in technical terms it's a transaxle as opposed to a transmission, cause it's more than just a transmission. But for FWD, calling it the transmission (or gearbox) is techincally right, cause you really can't do it any other way than the transaxle system.

Ya, don't worry about the LSD mention, that's just part of my quote from a previous post.

It's not the tranny and the diff that need to match, but the gearset and the differential have to. HOWEVER, *IF* you can take off the pinion gear and swap it to match the diff, than you can use whatever gearset you want, but changing the pinion gear is suppose to be a pain.

One could swap out the 5th gear for a lower engine speed at highway cruising speeds (and top speed, I guess) as well as a diff with a... lower gearing ratio? to add to the effect?

The 5th gear, yes, that would do it. With a lower ratio diff AND matching pinion gear, that would make ALL gears ratio lower, which would make that swapped 5th gear you put in even lower.

Just talking to myself, helps me understand, but I'm gonna click the submit button anyway so you can correct me if I'm wrong.

Makes sence, and it helps us know what your thinking and hopefully give you the info so you fully understand

[Ryan]

The transaxle, for a FWD car, basically it IS the tranny, it's the whole thing.

On a RWD car, the tranny is just that, just the gears. Than you have the driveshaft, the rear differential than the rear axles. In a FWD car, that's all-in-one, why in technical terms it's a transaxle as opposed to a transmission, cause it's more than just a transmission. But for FWD, calling it the transmission (or gearbox) is techincally right, cause you really can't do it any other way than the transaxle system.

It's not the tranny and the diff that need to match, but the gearset and the differential have to. HOWEVER, *IF* you can take off the pinion gear and swap it to match the diff, than you can use whatever gearset you want, but changing the pinion gear is suppose to be a pain.

One could swap out the 5th gear for a lower engine speed at highway cruising speeds (and top speed, I guess) as well as a diff with a... lower gearing ratio? to add to the effect?

The 5th gear, yes, that would do it. With a lower ratio diff AND matching pinion gear, that would make ALL gears ratio lower, which would make that swapped 5th gear you put in even lower.

Okay, so I still think the diff is a seperate unit from the transmission. They are seperable?

Okay, did more research

A pinion shaft and gear comming from the tranny power the diff. the pinion gear drives the ring gear, which is attatched to the drive shafts via more pinion gears.
the drive pinion mating to the ring gear are the 'final drive' ratio

what I don't understand is how the two pinions connecting the right and left wheels decide when to slip... wait. just thinking about it i get it. when the traction differs, they slip accordingly.... and this is why they spin opposite ways when both in the air... coool....

So we can only apply as much torque as the wheel with the LEAST traction can handle? dumb. thats what LSD's are for... or diff locks.


Wouldn't swapping the ring gear/drive pinion be difficult? wouldn't it be better to just swap the entire differential?

What are spider gears?

Wouldn't changing the final drive... make 1st gear seem more like 2nd? or would it make even lower? Obviously that matters if you swap to a higher or lower geared diff.

", *IF* you can take off the pinion gear and swap it to match the diff, than you can use whatever gearset you want, but changing the pinion gear is suppose to be a pain.
"

Change the pinion to match a diff. a lower diff? or higher? i can't remember which I want. I want to make my 5th gear run at lower RPM's. from an MX-6, right? but that wouldn't work because I have a 4 cyl...

is there a diff like that for the 4 cyls? Would it not be hard on my tranny to gear it so differently? I understand if you have a low rev input to a high rev output, it puts strain on the parts....

Same idea as last time, posting my thoughts

[Nd4SpdSe]

I gotta fly out in the morning, than work once i land, so I'll respond back when I get a chance to sit down and with the internet.

[Volones]

If you're looking to reduce your engine RPM at highway speeds, the best method would be to swap to a 'taller' 5th gear. There is a walk through available (I think on a protege forum) that shows how to do it.

I have also researched this, and I believe that the transmission from an early 90s protege with the 1.8L SOHC engine will work, but you'll need to change the clutch housing so it will bolt up to your engine again. I've looked at both transmissions in a scrap yard and where the transmission bolts to the clutch housing looks exactly the same to me. I will be doing this when my transmission finally gives up (soon I hope), and expect that the protege's 3.6:1 final drive will put my engine rpms at around 2,500 at 60mph (it's been a while since I played with the numbers, so I may be a little off). The only other option that I could find is the f-series transmission from a 1.5L B-series engine, which should have a 3.4:1 final drive. I couldn't find one of those transmissions locally, so I have no idea how close it would be to fitting.

Good luck,
Vol

[wytbishop]

The transaxle, for a FWD car, basically it IS the tranny, it's the whole thing.

On a RWD car, the tranny is just that, just the gears. Than you have the driveshaft, the rear differential than the rear axles. In a FWD car, that's all-in-one, why in technical terms it's a transaxle as opposed to a transmission, cause it's more than just a transmission. But for FWD, calling it the transmission (or gearbox) is techincally right, cause you really can't do it any other way than the transaxle system.

It's not the tranny and the diff that need to match, but the gearset and the differential have to. HOWEVER, *IF* you can take off the pinion gear and swap it to match the diff, than you can use whatever gearset you want, but changing the pinion gear is suppose to be a pain.

One could swap out the 5th gear for a lower engine speed at highway cruising speeds (and top speed, I guess) as well as a diff with a... lower gearing ratio? to add to the effect?

The 5th gear, yes, that would do it. With a lower ratio diff AND matching pinion gear, that would make ALL gears ratio lower, which would make that swapped 5th gear you put in even lower.

Okay, so I still think the diff is a seperate unit from the transmission. They are seperable?

Okay, did more research

A pinion shaft and gear comming from the tranny power the diff. the pinion gear drives the ring gear, which is attatched to the drive shafts via more pinion gears.
the drive pinion mating to the ring gear are the 'final drive' ratio

what I don't understand is how the two pinions connecting the right and left wheels decide when to slip... wait. just thinking about it i get it. when the traction differs, they slip accordingly.... and this is why they spin opposite ways when both in the air... coool....

So we can only apply as much torque as the wheel with the LEAST traction can handle? dumb. thats what LSD's are for... or diff locks.


Wouldn't swapping the ring gear/drive pinion be difficult? wouldn't it be better to just swap the entire differential?

What are spider gears?

Wouldn't changing the final drive... make 1st gear seem more like 2nd? or would it make even lower? Obviously that matters if you swap to a higher or lower geared diff.

", *IF* you can take off the pinion gear and swap it to match the diff, than you can use whatever gearset you want, but changing the pinion gear is suppose to be a pain.
"

Change the pinion to match a diff. a lower diff? or higher? i can't remember which I want. I want to make my 5th gear run at lower RPM's. from an MX-6, right? but that wouldn't work because I have a 4 cyl...

is there a diff like that for the 4 cyls? Would it not be hard on my tranny to gear it so differently? I understand if you have a low rev input to a high rev output, it puts strain on the parts....

Same idea as last time, posting my thoughts

Yes the Differential is a separate part. It can be removed from the transmission as an assembly. In order to change the final drive gear ratio, you would have to replace the differential and the pinion gear which drives it. Remember that the pinion gear is on the output shaft of the transmission and the speed of that shaft is determined by the ratios of the gear sets which make up the drive gears. Now if you put a differential and pinion gear in the tranny with a different final drive ratio, the output shaft is still spinning at the same speed, but the rotational speed of the differential itself, and in turn the drive axles will be changed, regardless of what gear is selected. This is what they mean when they say that lowering the final drive ratio lowers every gear.

If you just change the 2 cogs which are 5th gear and nothing else, you will only change the speed of the output shaft of the transmission and only in 5th gear. This has been commonly done for a long time using the 5th gear cogs from a MX-6 or 626 tranny.

The Spider gears are the cogs inside the differential which create the "limited slip" action of the diff. The drive shaft splines engage splines on the inner bore of the spider gears. The beveled teeth on the outside of the spider gears engage each other through the slip assembly (our trannies are "Open" diffs, so basically total slip. The opposite would be POSI which is zero slip). The interior of the diff is complex...I couldn't explain it adequately.

The only reason to change the diff and pinion gear would be to install a LSD diff, which for the G series tranny are only available with the 4.11 ring gear. So if you have a tranny with a 4.38 diff and you want LSD, you'd have to change the pinion to use the MazdaSpeed or Quaiffe LSD 4.11 diff.

All of the G-series trannies have the same input and output shaft components regardless of 4 cyl or 6 cyl. Your 4 cyl MX-3 has an F-series tranny. If you install a G-series from a Protege BP car (among others), then you could use the internals from any G tranny. I don't know anything about the ratios or interchangeability of the F trannies.

[Ryan]

You guys all rock. I can always read something somewhere and understand it, but its nice to have reassurance from people I actually trust, and know, and can blame if it screws up I think when I go BP I'll do a fifth gear swap... and leave the diff as whatever came with that tranny. Nnot sure where exactly to get the gears yet, I was thinking 626. Do the v6 MX-6 and 626 and MX3 use the G series tranny? I would think a tranny could not bolt up to a 4cyl and a v6, I would think they would be different?