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1991 2.2L AWD Legacy Automatic Transmission


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Hi!

 

I'm new here but a long standing member of Ford Forums. Which is ironic since I've had my Subaru longer than my Ford.

 

Does anyone know whether the Duty Solenoid C which controls the drive to the rear wheels needs 99% duty cycle to engage the clutch or 0%? I think it's 0% since the car is supposed to be towed with all 4 wheels off the gound which would indicate that with the ignition off the clutch would be engaged hence the rear wheels would drive the trans if it was to be towed with just the front wheels raised.

 

The reason I ask is this. Today the front diff (I think) went ping. I believe it's got a missing pinion tooth. It started a a chatter on deceleration about 3 weeks back so I thought it was just a chipped tooth on the trailing edge of a crown wheel - but it seems like it may have been more like a crack which has become a broken tooth.

 

Anyway I've always wondered what the car would be like as a RWD. I'm going to pull the trans tomorrow for diagnostic purposes and I may well try to change the car to RWD only.

 

I wonder if the rear diff can handle all the power on it's own (not that there's much power - couldn't pull the top off a rice pudding).

 

Also - does anyone know what the ratio on the diff is? I know the NA's are taller geared than the turbos. I could wait until I get it out but I'm impatient! Actually I'd like to try to price one to see if it effects my decision to go RWD.

 

Thanks in advance!

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100% duty of the duty c solenoid will give you zero torque to the rear wheels. 0% duty will give you full line pressure to the rear clutch plack, and essentially 50/50 torque split.

 

The towed with all four wheels off the ground is due to the automatic and it having AWD. You can tow a MT AWD car with all four wheels on the ground for a short distance.

 

With the way the automatic transmission is designed, you won't be able to convert it to RWD. The RWD comes from an extension housing on the rear of the transmission that is fed transmission line pressure through the duty c solenoid to a set of clutch packs.

 

Check out these scans for more detailed info

http://main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/AWD_transfer_system1.jpg

http://main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/AWD_transfer_system2.jpg

http://main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/AWD_transfer_system3.jpg

 

The rear diff can handle the power....the clutch packs are what can't handle it.

 

the final drive ratio on the n/a legacies 90-91 MT's & AT's are 4.111. The final drive ratio on the n/a legacies 92-94 AT's are 3.900. n/a legacies 92-94 MT's are 4.111. turbo legacies 91-94 are 3.900.

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I figured the way to do it would be leave the reduction gear off the shaft that transfers torque to the front differential & disconnect the Duty Solenoid C (replacing it with similar resistance to fool the computer). But that relied on the clutch pack being able to take the full power, which you say it isn't capable of.

 

So instead I may have to get a second transfer clutch basket assembly & look at welding it up. Then if it breaks I can put my one back in with the reduction gear without dropping the trans.

 

Sound like a plan to you? I have a second car so there's no real worry - it's just something I've always wanted to try. Since the Subaru's up to 260k now it's getting a bit tired anyway.

 

Thanks for your input - much appreciated.

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there's a fuse that technicians have for diagnostic purposes that plugs into the engine bay that converts the car to fwd. Not possible to go rwd

 

sorry i cant be of help, but here's some mighty useful information...

your power splits go as so

 

Automatic:

1st and 2nd - 50front/50rear

3rd and 4th - 90front/10rear

(used for fuel economy on the freeway, you dont need a 50/50 split going that fast)

 

Manual

1st-5th 50front/50rear

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find a way. My brother in law owns Pegasus in Queenstown and if you wish I could see if Norm has a line on some cheap bits. Last I knew he was using all five speeds though.

Does not seem that you would want to invest the time and effort into it with that many ks on it, but the fun factor enters into it too.

I personally did a number of pointless conversions when I was a kid because I enjoyed doing it.

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  • 8 months later...

I found the thread:

 

FAQ's

 

Why did you do this modification?

 

My front diff was going out and I needed my car so without spending heaps I figured if I can allow the front Diff to spin freely it will be fine. So the Idea of building a RWD SVX was born

 

How did you do the modification?

 

I took the output shaft out of the transmission removed the drums and clutches and welded the shaft solid removed the front CV axles kept the cups in the wheels to support the bearings.

 

How much did this cost you?

 

So far nothing but It was a lot of work. I am going to split the shaft in 2 balance and reweld the shaft which should be about $100

 

If you now have a new transmisson why is it still Rear wheel drive?

 

Well the Outback trany has a low gear ratio which would cause the SVX to run high Rpm at high way speeds

 

Can I do this my self?

 

Disclamer: NO I do not recomend anybody try this at home it can ruin your transmission or seriously damge it if done wrong!

 

What kind of power diffrence did you notice?

 

well the gain was signifigant I can't think of any mod to a SVX besides nitrous turbo or supercharger that would make as much of a power difference.

 

Can you do a Burnout?

 

Piece of cake

 

BTW the car handles as well if not better being RWD but a heavy right foot at the wrong time can spin you in a circle

 

Also I will be changing My SVX to 3.700 gear ratio in plac of the stock 3.545 ratio

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