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Does anyone knows who has the best deal for the Quaife Lsd? I'm looking to buy one soon. Thanks for ou help
 

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I'd give Terry a call. I think he'll cut you a deal on the Quaife if you have him do the installation.
 

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i've had a question about one of these. does it make a big difference on straight line driving? i dont really care about turns and what not i was jw if it would improve your hp at the wheel?
 

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DoubleStuf™
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My understanding is that it would give you the traction of both front wheels instead of only one. So you could put more HP to the ground because if you're going to spin wheels, with a LSD you've got to have enough HP to spin BOTH wheels, not just one (like with an O.D.)
 
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I got mine from Options Auto Salon, cheapest I could find for the SVT.
 

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My understanding is that it would give you the traction of both front wheels instead of only one. So you could put more HP to the ground because if you're going to spin wheels, with a LSD you've got to have enough HP to spin BOTH wheels, not just one (like with an O.D.)
You won't need more power. But I can see how one could be confused. An LSD will not require more power, but the more power you have the more the open differential will become a problem.

The stock differetial is an open (aka "dog leg") diff. It will divert power to the path of least resistance, the wheel getting the LEAST traction. That means if you go into a corner hard you will be more likely (read: you WILL) spin wheels and not really put any power to the ground. This is because the job of the differential is to apply equal power to both wheels. So when one wheel is spinning the opposite will get the same power and your car will not accelerate, or at least not accelerate very fast. When driving in a straight line on smooth pavement, an open diff should allow power to go to both wheels as long as they are not spinning. The problem is you will probably spin even in a straight line. So in drag racing your car will only have as much power as the wheel getting the least traction, meaning less acceleration. The issue comes in when you turn or one wheel loses traction, the open diff will only allow the power to apply as much as the wheel with the least traction. If you were to drive your car so that one side was on pavement and one on ice, the open diff would only allow power to be applied to the pavement wheel equal to that of the ice wheel. I mentioned before that more power will increase the problems of an open differential, the reasons should now be clearer. When hard driving through turns with stock power, a Focus may not overpower its tires very easily so they might not spin. With a lot of power, the car will be more able to break one of the drive wheels loose and understeer.

With a limited slip, the power will not be equal between the wheels. So if you enter a turn and one wheel spins, the other wheel will get more power rather than equal power as with an open diff. A Quaife or Torsen (the two available for our MTX75) will always bias the power to the wheel with the most grip. So instead of going into a turn and underdriving because the open diff is allowing the wheel with the least traction to spin, the LSD will send power to the wheel with the most grip. Now, go back to the ice example, the LSD will allow the pavement wheel to have more power (about 5X as much) as the wheel spinning on the ice. So your car will be able to accelerate much quicker even though half of your drivetrain is spinning on ice.

IMO an LSD is a "must have" on any car, especially one that will be driven in any kind of racing conditions.

I'm still running an open diff because I don't have the money to get an LSD, much less have it installed. So for now my car "peg legs" it off the line at the track, understeers in hard cornering like a bastard, and plows or doesn't move in the snow. One day though...

EDIT: sorry for the long post, but it's not a simple one line answer kind of subject.

Nate
 

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Don't Call Me Gaga!
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Good description, except for the ice. The Torsen T-2 (and probably the Quaife as well) will fail the "one wheel on pavement, one on ice" test, because it needs *enough* grip to operate as an ATB LSD.

This isn't speculation, Torsen actually publishes this info. The Torsen T-2R has some sort of strange preload that will allow it to operate on the ice/pavement environment. The T2-R isn't available for a Focus, however.

I assume a Quaife is the same way. I've autocrossed a car that spun the inside tire with a Quaife because it was so far unloaded that it didn't have enough grip to function.
 

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Omni - in those situations where one wheel has prettymuch zero traction, have you ever tried lightly applying the brakes to put a little load on the differential?

Related side note: on a traction-control-equipped Focus, it would theoretically be possible to program the system to improve the performance of an ATB differential, wouldn't it?


Not exactly a DIY project, but it's a cool idea. For all I know, maybe some OEM's already do that.
 

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Don't Call Me Gaga!
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Related side note: on a traction-control-equipped Focus, it would theoretically be possible to program the system to improve the performance of an ATB differential, wouldn't it?


Not exactly a DIY project, but it's a cool idea. For all I know, maybe some OEM's already do that.
Good thinking... that'd be fairly easy with the right software.
 

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just out of curiosity......do LSD's do better in the snow/rain then a O.D? or does the O.D do better then LSD in the rain/snow?
 

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....ours is under $600 if we fit it....
Sure are you going to fly over and install it?
 

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....ours is under $600 if we fit it....
Sure are you going to fly over and install it?
I second the notion! I am also in Germany wanting an LSD! Plus new clutch! So, that's two customers for you KogboxKing!
 

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Discussion Starter #17
....ours is under $600 if we fit it....
Sounds like a great deal. But where are you guys located, and how much is the install?
 

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He's in Michigan - near Grand Rapids, I think. Generally, people pull the tranny themselves and ship it to Terry for the rebuild.

If you're interested, just call or e-mail him. I know he's having some family issues lately (his father-in-law's health, IIRC), so cut him a little slack if he doesn't get back to you right away.
 

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Discussion Starter #19
He's in Michigan - near Grand Rapids, I think. Generally, people pull the tranny themselves and ship it to Terry for the rebuild.

If you're interested, just call or e-mail him. I know he's having some family issues lately (his father-in-law's health, IIRC), so cut him a little slack if he doesn't get back to you right away.
Cool, thanks
 
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