1G N/t Transmission in Turbo Car?

[slammed608]

Heres the rundown 1990 Plymouth Laser Rs turbo FWD.. put a trans in it that i had...no good. Not really trying to buy a transmission gear/bearing set so i figure id look for another trans and came across a 1991 Eclipse GS (Non turbo)... will the trans fit? i know sensors and speedo cable are the same but ill probably need the flywheel and starter plate too but other than that will it bolt up?! and yes i know the N/A trans are weaker but hell

 

[Soccerguy136]

1st: You are a fool for doing this. Even the early fwd TURBO transmissions had problems holding stock power so they upgraded the axles around 93. It is a stupid move.

That said...

2nd: Yes, it will physically bolt up. You would need the starter plate, clutch, pressure plate, and flywheel from the GS. Starters are the same.

 

[serviceguy]

1st: You are a fool for doing this. Even the early fwd TURBO transmissions had problems holding stock power so they upgraded the axles around 93. It is a stupid move.

Uhmm, was the transmission not holding stock power or were the axles?

 

[curt-s]

Where can we find information about your #1 point? First I've heard that a 91 FWD transmission can't hold ~200ft/lb.

 

[codym]

Heres the rundown 1990 Plymouth Laser Rs turbo FWD.. put a trans in it that i had...no good. Not really trying to buy a transmission gear/bearing set so i figure id look for another trans and came across a 1991 Eclipse GS (Non turbo)... will the trans fit? i know sensors and speedo cable are the same but ill probably need the flywheel and starter plate too but other than that will it bolt up?! and yes i know the N/A trans are weaker but hell

I'd be extremely gentle on it, even if it's only temporary.
The bolt patterns are identical to eachother, you will need the items soccerguy posted.

Unless your getting all this for a great deal it might be more cost effective to get the turbo trans rebuilt. There are several vendors on here who do stock rebuilds, and if you would rather buy a used trans, Miller Import Parts usually has working transmissions in stock..

 

[92AWDHX40]

I did this for a while when I did my non turbot to turbo swap trans lasted for a few months.

 

[DSM1G90]

Turbos FWD's ran the heavier and stronger F5M33 trannies that are geared a bit lower than the weaker and higher geared F5M22 trannies used in the NT vehicles.

Also, the "33" trannies used stronger Timken tapered roller bearings, whereas the other used standard roller bearings.

 

[Soccerguy136]

Where can we find information about your #1 point? First I've heard that a 91 FWD transmission can't hold ~200ft/lb.

Can you think of a different reason as to why Mitsu upgraded the size of the axles and did a transmission redesign around 92 for the FWD turbo cars...

Uhmm, was the transmission not holding stock power or were the axles?

And how, pray tell, is he supposed to use the larger axles in his earlier transmission. Whether it was early axles or early transmission, the result is the same...

Anyway, my main point was that if the stock transmission/axles are barely capable, and he is switching to a transmission even weaker than that, he is making the wrong choice. I was just trying to save the OP some headache down the road when it starts having problems down the road from blowing the trans, axles, clutch, etc. since it was far from designed for the task he is asking it to perform.

 

[serviceguy]

And how, pray tell, is he supposed to use the larger axles in his earlier transmission. Whether it was early axles or early transmission, the result is the same...

He can't, that is not what I was saying. What I am saying is that bigger size axles do not make a stronger transmission as you seem to suggest. While being part of the drivetrain, axles are not part of the transmission. I any case 91 axles were not beefier than the 90 ones.

 

[Soccerguy136]

He can't, that is not what I was saying. What I am saying is that bigger size axles do not make a stronger transmission as you seem to suggest. While being part of the drivetrain, axles are not part of the transmission. I any case 91 axles were not beefier than the 90 ones.

You're missing my point. No, there is no difference between 90-91 axles. No, axles do not make a trans stronger. I never implied that. I said that the result is the same, as in, a problem holding power without breaking. Whether the axles break or the trans breaks, it is a problem. That's most likely why they redesigned the transmission AND increased the axle size in 92 without changing the power output, clearly suggesting they were both problem points in early turbo cars.

Like I said earlier, my main point was just to dissuade the OP from doing this swap, not get into a debate about how strong the early turbo axles and transmission are.

 

[serviceguy]

You're missing my point. No, there is no difference between 90-91 axles. No, axles do not make a trans stronger. I never implied that. I said that the result is the same, as in, a problem holding power without breaking. Whether the axles break or the trans breaks, it is a problem. That's most likely why they redesigned the transmission AND increased the axle size in 92 without changing the power output, clearly suggesting they were both problem points in early turbo cars.

Like I said earlier, my main point was just to dissuade the OP from doing this swap, not get into a debate about how strong the early turbo axles and transmission are.

Honestly that is not what comes through reading point 1 of your first post.

Again, besides changing the axle hubs for a bigger size, was the fwd turbo transmission redesigned or made stronger in 92?

My point is that the OP idea may not be advisable especially in the long term as opposed to an emergency/cheap fix, but proven facts should be used in order to dispute it instead of very arguable speculations.

Nothing wrong with debating anyway.

 

[Boost Solution]

F5M22 fwd na is very fragile the break a lot in my colt 4g63t
the f5m33 fwd turbo is very good trans

f5m22 300fwhp 205/55/15 radials

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f5m33 96-99
nice fwd gearbox double syncro second gear bing syncro rings 3&4

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[thomcasey]

90 FWD trannies are a little weaker than the 91+ models. They also use different shifters and cables/cable mounts on the transmission.

the axle spline count change in the 93/94 transmissions was NOT for power handling, otherwise they would have kept in 95-99. It just created a headache for car owners that now had to either find the special axles, or swap out the diff from a different tranny to get the smaller spline count.

f5m33 is your strongest FWD transmission. Next id the f5m31/KM-210 transmission (came on the Colt-GT turbo in 89). f5m22 is definitely a non-turbo application only.

 

[serviceguy]

Just to be clear I do not believe that installing a 1g n/a transmission in a 1g turbo powered car is a good idea, not at all. The two previous posts made it quite clear.

It should also be kept in mind that the OP wasn't planning to have any more than stock power. That said, if the n/a transmissions had been good enough for the turbo engine Mitsubishi wouldn't probably have gone through the hassles of designing a new one.

 

[Soccerguy136]

Honestly that is not what comes through reading point 1 of your first post.

Again, besides changing the axle hubs for a bigger size, was the fwd turbo transmission redesigned or made stronger in 92?

My point is that the OP idea may not be advisable especially in the long term as opposed to an emergency/cheap fix, but proven facts should be used in order to dispute it instead of very arguable speculations.

Nothing wrong with debating anyway.

The transmission's were redesigned in 92 yes, and I have seen somewhere that they made it stronger, but I don't have any concrete proof offhand of what it was from Mitsubishi, which seems to be what you are looking for.

90 FWD trannies are a little weaker than the 91+ models. They also use different shifters and cables/cable mounts on the transmission.

the axle spline count change in the 93/94 transmissions was NOT for power handling, otherwise they would have kept in 95-99. It just created a headache for car owners that now had to either find the special axles, or swap out the diff from a different tranny to get the smaller spline count.

f5m33 is your strongest FWD transmission. Next id the f5m31/KM-210 transmission (came on the Colt-GT turbo in 89). f5m22 is definitely a non-turbo application only.

I am fairly certain there are only two axle sizes/splines available for a Fwd turbo Dsm. The ones that match up with the awd splines in 90-early 92, and the larger and different splined ones in late 92 -99.

DSM Forums: Mitsubishi Eclipse, Plymouth Laser, and Eagle Talon Forum: DSMtalk.com - View Single Post - 1g Turbo FWD transmission axle differences?

 

[curt-s]

F5M22 fwd na is very fragile the break a lot in my colt 4g63t
the f5m33 fwd turbo is very good trans

f5m22 300fwhp 205/55/15 radials

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f5m33 96-99
nice fwd gearbox double syncro second gear bing syncro rings 3&4

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Ok so a 22 sheared at 300whp. No surprise there, but we don't know the details behind how exactly it was being driven at the time.

The original statement was that an early turbo trans couldn't hold stock power.. I, frankly, call BS on that any which way you look at it, regardless of redesign. There's a million reasons why something is redesigned, even down to what they can get from a manufacturer, or making components as universal across multiple platforms as possible.
Otherwise, if there was a problem with stock power handling, there wouldn't be any 90/91 transmissions left on the road and there should be a slew of TSBs, including transmission gearset replacement. You know, just like the issues with the transfer cases.

Stock power, driven like a non-idiot, I don't see any of the DSM transmissions having an issue. Start putting more power than they were designed for through them, of course you're going to run into issues eventually. That's true of any transmission. Even mighty Godzilla.

Anyway, because the 22 was designed with NT power in mind, I would not suggest them as a long term replacement for a 33. It'll last longer if you're kind to it. That is, if you're really interested in putting a 91 NT trans into a 90 bay. Just don't wheel hop, or you'll walk home.

 

[DSM1G90]

If he was going to use the F5M22 tranny, at least disable the turbo by wire open the wastegate so he can easily stay out of boost.

He'd have lower torque range due to the lower compression ratio the turbo motor has (7.8:1) than the NT's 9.0:1 compression ratio.

Just have to keep out of WOT and shift easy to make it work okey until he gets his turbo tranny repaired.

-DSM

 

[92AWDHX40]

Wow that's some damage there.