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Old 08-17-2007, 05:29 AM   #21
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Quote:
Originally Posted by boxsterz
I thought the opposite was true, that an ATB sends torque to the wheel that has the most grip?
Torsens only send torque to the wheel with the most grip if theres SOME torque on both wheels. The clutch type LSD can do it when there's no torque on the gripping wheel. This is how you can get an open diff on corner entry but an LSD on exit.

However, if you slightly touch the brakes while one wheel is slipping, you can get torque to the gripping wheel with a Torsen.

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Old 08-17-2007, 05:35 AM   #22
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Quote:
Originally Posted by blue2000s
Torsens only send torque to the wheel with the most grip if theres SOME torque on both wheels. The clutch type LSD can do it when there's no torque on the gripping wheel. This is how you can get an open diff on corner entry but an LSD on exit.

However, if you slightly touch the brakes while one wheel is slipping, you can get torque to the gripping wheel with a Torsen.
Exactly!

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Old 07-15-2008, 09:26 PM   #23
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Question

So what type of LSD would help the Boxster get better traction if driven in snow and ice? (with proper winter tires of course)
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Old 07-16-2008, 05:53 AM   #24
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Quote:
Originally Posted by Jacques79
So what type of LSD would help the Boxster get better traction if driven in snow and ice? (with proper winter tires of course)
The best solution for this is traction control.

I don't like either LSD on snow or ice. Clutch type will induce oversteer (which I've experienced first hand, many times, on my AWD car with an open front and clutch type rear) and a torque biasing will usually act as an open diff.

Answering this in another way, a torque biasing LSD probably won't hurt, but it probably won't do much to help in snow and ice. But it would be a lot of fun on dry roads. A clutch type can lead to instability in slippery conditions, which, in a mid-engine car could be dangerous.
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Old 07-16-2008, 06:36 AM   #25
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Red face

Quote:
Originally Posted by blue2000s
The best solution for this is traction control.

I don't like either LSD on snow or ice. Clutch type will induce oversteer (which I've experienced first hand, many times, on my AWD car with an open front and clutch type rear) and a torque biasing will usually act as an open diff.

Answering this in another way, a torque biasing LSD probably won't hurt, but it probably won't do much to help in snow and ice. But it would be a lot of fun on dry roads. A clutch type can lead to instability in slippery conditions, which, in a mid-engine car could be dangerous.

I appreciate your input a lot and you seem to know your stuff, but what I'm looking for is an LSD that would help me from a standing start; if I start up my car and there's snow and ice under the rear wheels, would an LSD help BOTH wheels spin at the same time?

Because last winter it was pathetic to see only one rear wheel spinning at a time when people tried to push my car to when I got stuck

I remember when I had an S2000 (which has TORSEN LSD) I would almost never get stuck in snow-ice.

Both my Boxster S and S2000 had the exact same kind of winter tires with same width on the rear wheels.

If this doesn't make any sense and an LSD would only help for when you're driving at speed in snowy conditions please pardon my ignorance
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Old 07-16-2008, 07:42 AM   #26
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Quote:
Originally Posted by Jacques79
I appreciate your input a lot and you seem to know your stuff, but what I'm looking for is an LSD that would help me from a standing start; if I start up my car and there's snow and ice under the rear wheels, would an LSD help BOTH wheels spin at the same time?

Because last winter it was pathetic to see only one rear wheel spinning at a time when people tried to push my car to when I got stuck

I remember when I had an S2000 (which has TORSEN LSD) I would almost never get stuck in snow-ice.

Both my Boxster S and S2000 had the exact same kind of winter tires with same width on the rear wheels.

If this doesn't make any sense and an LSD would only help for when you're driving at speed in snowy conditions please pardon my ignorance
I don't how the LSD on an S2000 works, Honda may have added some electronic traction control features to supplement the torque sensing diff? That would be the best way to go.

To answer your question, the clutch type differential is better at getting you out of a situation where only one wheel has traction. But you need to think about all the ways you use the car in the winter. It's not just starting and stopping.

As an extreme example, you could get better traction in snow and ice by having no differential at all. Both wheels will spin at the same speed all the time, but as soon as you try to turn, you will be running off the road.
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Old 07-16-2008, 08:41 AM   #27
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Quote:
Originally Posted by blue2000s
I don't how the LSD on an S2000 works, Honda may have added some electronic traction control features to supplement the torque sensing diff? That would be the best way to go.

To answer your question, the clutch type differential is better at getting you out of a situation where only one wheel has traction. But you need to think about all the ways you use the car in the winter. It's not just starting and stopping.

As an extreme example, you could get better traction in snow and ice by having no differential at all. Both wheels will spin at the same speed all the time, but as soon as you try to turn, you will be running off the road.

Thanks I appreciate your input a lot! That's the exact answer I was looking for.

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Old 07-18-2008, 08:51 PM   #28
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I'm likely sending my 6-speed box to GBox to be freshened, and while its there I'm leaning toward having a Quaife installed. Looking at around $2k for freshening (assuming they don't find anything damaged in there) and another $2k for the Quaife and its installation. Blueprinting is available for an extra $250 and they claim its a substantial improvement in shift feel.

Patrick

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