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40% LSD, what does it ACTUALLY mean?

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Old 05-25-2002, 12:04 PM
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mmmbeer
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Post 40% LSD, what does it ACTUALLY mean?

I do know what an lsd is and how it works, but what does the percentage stand for. 40% or 100% what is the difference?

My guess is that a 40% lsd will allow 40% difference in wheel rotation before it start working. Ergo is a 40% lsd working sooner than a 100% lsd. Or am I wrong about that?

Eirik Kvello-Aune
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Old 05-25-2002, 12:52 PM
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d richard
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I always thought it was 40% LOCKUP
Old 05-25-2002, 02:08 PM
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adrial
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I think it is 40% lockup.

Which I think means that lets say one wheel has traction and the other doesn't. The LSD will be able to give 40% of the power to the wheel that grips...I'm not really sure though.
Old 05-25-2002, 03:40 PM
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Tom Pultz
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LSDs used in racing can go as high as 80% or so. If you think of a fully locked differential as 100%, the 80% LSD only allows for a 20% difference between wheel speeds before they are "locked." This would not work on the street, but is OK for some tracks.

The typical true street LSD is about 40% like you say, and this allows for 60% slip.

Most LSDs can be adjusted by fitting different shims and/or clutch plates to change the lockup characteristics.
Old 05-25-2002, 05:01 PM
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GTL
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There is an excellent article about LSDs at:

<a href="http://members.aol.com/agspeed/LSD-lock.htm" target="_blank">http://members.aol.com/agspeed/LSD-lock.htm</a>
Old 05-25-2002, 05:17 PM
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mmmbeer
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Thanks guys. Now I get it.

Eirik Kvello-Aune
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