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Discussion Starter #1
I'm looking for a junked MS6 (hopefully not many but I know of at least one or two) I'm trying to get a read diff from one so that I can work on making a part for the car. I would need the entire rear diff. The part that connects to the driveshaft all the way back. Dont need axles.

I'm wondering if anyone would be interested in making their/our cars 4wd or awd all the time. Making it 4wd is the easier part and what I will probably work on first. Making it awd (meaning it would have a center diff) would be the harder part but I believe is possible. I want a diff though so I can pull it apart, make some measurements and find out how I would need to connect the parts. Designing the part will be easier and only requires my time. Making the part would be cost of material. I have access to a machine shop so no problem there.

I know though making the car full time 4wd/awd could cause problems with the system. Since its not meant ot be in that mode all the time. I"m not sure what would happen if the electromagentic clutch was disconnected. The light may come on, but not sure what else it would affect.

Anyway, if anyone knows where I may be able to find a diff let me know or if they know of any MS6's that have been totalled already. i know of one but cant remember where I saw the pictures of it.

Thanks.
TJ
 

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Good luck.

If you ever get it off the ground, perhaps shorting out the e-brake switch would help deal with the ECU.

It would put it in "fwd" mode, even though it would still be attached to your center differential and working the back wheels.

Might avoid throwing a CEL
 

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Discussion Starter #3
Good luck.

If you ever get it off the ground, perhaps shorting out the e-brake switch would help deal with the ECU.

It would put it in "fwd" mode, even though it would still be attached to your center differential and working the back wheels.

Might avoid throwing a CEL
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Somewhat what I was wondering. Does the DSC and ABS still work even if there is a problem with the 4wd? Other option would be to just pull the fuses for those items, but then you would not have those working.

I'm open to possible ways of getting around that part, or maybe somehow making the computer think its in 4wd all the time, still use fluid in the case but it would never get hot so the computer would not think anything would be wrong with it. I think the problem will be more in not having the electromagnetic clutch hooked up.

Basically, thats the part I see as possibly being the bigger problem. If we can make the ecu think its in 50/50 split, then it could be fine.
 

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ABS should work fine, but I would say that there's probably a slim chance in hell you'll get DSC working properly.
 

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Making full-time AWD would be really cool, but I cannot imagine how incredibly expensive this would be to fabricate. Even once fabricated, I'd be paranoid about durability.

4WD would render the car almost undrivable on dry pavement... not sure what your goal is there except for R&D to lead to proper AWD.

Anyway, if you're serious about this, I'm definately curious to see how and what you do.
 

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Discussion Starter #6
Making full-time AWD would be really cool, but I cannot imagine how incredibly expensive this would be to fabricate. Even once fabricated, I'd be paranoid about durability.

4WD would render the car almost undrivable on dry pavement... not sure what your goal is there except for R&D to lead to proper AWD.

Anyway, if you're serious about this, I'm definately curious to see how and what you do.
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4wd would be no different than driving my talon with a spool instead of a center diff. People always complain that a spool makes driveability hard blah blah. The ONLY time you may have any kind of problem, would be when barely moving making very sharp turns, then you can feel it. Heck, when I had stickier tires I noticed it less than when I had harder tires. Until you have actually rode in a car with a spool or welded center diff, its not as bad as some people think it is.

Durability? If you saw the size of a spool, and how much power people make, the spool will be fine. And making the part should not be too hard. Hardest would be making the splines (have to find somewhere to do that part. Everything else on it would be using a lathe and a drill. The actual diff would be harder since finding something that would fit would be the problem and I have no idea how much room there is in the casing. Hence, why I need a rear diff to tear apart.

edit: Also, our cars are 4wd and not awd as we do not have a center diff.
 

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The DSC will do very funky stuff. THe DSC works by individual wheel braking. For example, with a welded diff, When it grabs a right rear wheel it will inadvertantly grab the entire drivetrain. FULL wheel independence is a requirment of the DSC system.

Driving a Locked 4x4 is DOOABLE but its not advisable. It is just like driving a part time manual 4x4, some say its not pleasant but other than that its kinda dangerous and makes the vehicle handle like shit in anything other than a straight line.
 

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4wd would be no different than driving my talon with a spool instead of a center diff. People always complain that a spool makes driveability hard blah blah. The ONLY time you may have any kind of problem, would be when barely moving making very sharp turns, then you can feel it. Heck, when I had stickier tires I noticed it less than when I had harder tires. Until you have actually rode in a car with a spool or welded center diff, its not as bad as some people think it is.

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I've got to strongly disagree here, my old Subaru wagon had real 4WD and it SUCKED to have it engaged on dry pavement, any steering input at any speed and you could feel the wheels fighting each other.
 

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Discussion Starter #9
I've got to strongly disagree here, my old Subaru wagon had real 4WD and it SUCKED to have it engaged on dry pavement, any steering input at any speed and you could feel the wheels fighting each other.
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I think that is more car related than 4wd related. Runnign a spool is the same as 4wd. 50/50 split all the time. Technically, the MS6 is 4wd as there is not center diff. There is nothing to let the rear wheels and front wheels spin at a different rate aside from not sending any power to the rear wheels. At that point, its not 4wd anymore.

I've never had any problem driving the talon anywhere. Hell giving it gas around a turn will kick the rear end out if I want it to.

I guess this would be more oriented for anyone who wanted to road race or by some odd chance, want to actually rally the car (though I highly doubt this)

Only time I've ever felt wheels fighting eac other is at very slow speeds. Otherwise the front and rear diffs do enough to let the wheels spin differently.

Either way, its something I plan to do regardless. And until its actually made and tested, we wont know.
 

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It also has to do with wheelbase. The longer the wheelbase the more binding because the diffrential speeds between the front and rear set of wheels are going to be greater.

NOBODY runs a road race with a locked center diff. Thats because it totally kills stability in at the limit cornering situations.

The reason why you were able to break the rear loose is because in cornering situations the front is trying to force the rears to move faster than it wants to turn.

In my experience with 4wd vs AWD cars a 4wd car will always be very loopy at the limit to the point where its unpredictable. ESPECIALLY in high speed sweepers.

Its NEVER a good thing when one set of wheels is trying to force another set of wheels to spin faster or slower than they want to spin. Pretty soon one set of wheels is going to give up traction because of binding and all control will be lost.

Here is the physics of the situation:

In cornering the progression of wheel speeds is as follows:

ouside front> oustide rear > inside front > inside rear

Disrupting the speed balance by linking the rear with the front will force the most unweighted corner in this case the inside rear to sync speed with the additive rotation speed of the front tires.

What you get is a transition of the inside rear tire from static friction to kinetic friction. For you non physics buffs all you have to know is static friction is greater than kinetic friction.

What you get in essence is similar to pulling the ebrake mid turn on the inside rear tire. Which may be "fun" in low speed situations but its downright dangerous at speed.


Offroad or drag race situations is a diffrent story though.


Im not trying to stop you from what you are doing but I want people to understand what such a device will do before putting it on thier list for thier "next greatest mod"


Additionally you will be essentially reducing the effectiveness of 2 important saftey systems in the car.

ABS: Works based on a speed differential between wheels. When there is a great enough speed diffrence between wheels it senses lockup and activates.

DSC: It is absolutely essential that this system has 4 fully independent wheels. It works by sensing speed diffrences between wheels, among other things. When it activates it changes dynamic behavior by applying brakes INDIVIDUALLY. If individual wheel rotation is effected the DSC will be useless if not dangerous. As its pre programmed responses will no longer be valid.
 

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Discussion Starter #11
It also has to do with wheelbase. The longer the wheelbase the more binding because the diffrential speeds between the front and rear set of wheels are going to be greater.

NOBODY runs a road race with a locked center diff. Thats because it totally kills stability in at the limit cornering situations.

The reason why you were able to break the rear loose is because in cornering situations the front is trying to force the rears to move faster than it wants to turn.

In my experience with 4wd vs AWD cars a 4wd car will always be very loopy at the limit to the point where its unpredictable. ESPECIALLY in high speed sweepers.

Its NEVER a good thing when one set of wheels is trying to force another set of wheels to spin faster or slower than they want to spin. Pretty soon one set of wheels is going to give up traction because of binding and all control will be lost.

Here is the physics of the situation:

In cornering the progression of wheel speeds is as follows:

ouside front> oustide rear > inside front > inside rear

Disrupting the speed balance by linking the rear with the front will force the most unweighted corner in this case the inside rear to sync speed with the additive rotation speed of the front tires.

What you get is a transition of the inside rear tire from static friction to kinetic friction. For you non physics buffs all you have to know is static friction is greater than kinetic friction.

What you get in essence is similar to pulling the ebrake mid turn on the inside rear tire. Which may be "fun" in low speed situations but its downright dangerous at speed.
Offroad or drag race situations is a diffrent story though.
Im not trying to stop you from what you are doing but I want people to understand what such a device will do before putting it on thier list for thier "next greatest mod"
Additionally you will be essentially reducing the effectiveness of 2 important saftey systems in the car.

ABS: Works based on a speed differential between wheels. When there is a great enough speed diffrence between wheels it senses lockup and activates.

DSC: It is absolutely essential that this system has 4 fully independent wheels. It works by sensing speed diffrences between wheels, among other things. When it activates it changes dynamic behavior by applying brakes INDIVIDUALLY. If individual wheel rotation is effected the DSC will be useless if not dangerous. As its pre programmed responses will no longer be valid.
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Understandable. Though had nto thought about the change from static to kinetic friction. Though the spool would be better for off-road cases or drag racing. The idea is its something that should be easy to put in and out.

Second part though about a differential there instead of the clutch mechanism. There are differentials that would probably fit the housing. Finding one to mate up to the input of the rear diff would be the harder part. Though assuming one could be found, I would think that would be better and would still allow the DSC and ABS to work.

Note: If I put a spool in, the DSC would be turned off.
Maybe its just me but I like how the talon drives with a spool in it. Maybe I just prefer driving it that way. Either way, it would help with moving to the idea of a center diff. Technically, the MS6 is 4wd because it has no center diff. Only reason some of the things can work the way they do is by cutting power to the rear wheels.
 

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I've got to strongly disagree here, my old Subaru wagon had real 4WD and it SUCKED to have it engaged on dry pavement, any steering input at any speed and you could feel the wheels fighting each other.
[/b]
I had a WRX wagon and it handled great, either on dry or wet pavement. Never felt the wheels fighting each other
 

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I had a WRX wagon and it handled great, either on dry or wet pavement. Never felt the wheels fighting each other
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The WRX does not have true 4WD. It has a viscous center differential that allows the front and rear wheels to spin at different speeds. In a true 4WD vehicle, there is no center differential.
 

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I'm wondering if anyone would be interested in making their/our cars 4wd or awd all the time. Making it 4wd is the easier part and what I will probably work on first. Making it awd (meaning it would have a center diff) would be the harder part but I believe is possible. I want a diff though so I can pull it apart, make some measurements and find out how I would need to connect the parts. Designing the part will be easier and only requires my time. Making the part would be cost of material. I have access to a machine shop so no problem there.
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It would probably be easier and simpler to rework the software that would allow the switch to snow mode manually. The hand brake does some wacky things on the MS6 and it might be possible to simply let the computer "think" that it is engaged...

I agree with others: Reworking hardware without software is going to create undesirable side effects. However, even if the software is tricked out, there could be hardware failures if the rear end and the whole system is "not designed" with 100% use in mind. My $0.02!
 

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The WRX does not have true 4WD. It has a viscous center differential that allows the front and rear wheels to spin at different speeds. In a true 4WD vehicle, there is no center differential.
[/b]
Exactly. Older Subbies used to have available true 4WD and a hi/lo range selection too.
 

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My X-Type had a full time 60/40 split rear/front. It handled great with that bias. Maybe you should find a junked X-Type.
 
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