Wtf is an LSD?

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chinchilla
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Post Sat Nov 04, 2006 1:34 pm

HELP please ive heard alot about this lsd stuff and differnt ratios etc on this forum.

So can some one please give me the low down on this? I know its something to do with axels or how the wheel spins.. but can some one explain in detail about this topic.. what ratio is good for a 1990 320i cab? how much does it cost?

thanks
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aled328
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Post Sat Nov 04, 2006 1:43 pm

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tim-ix
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Post Sat Nov 04, 2006 1:47 pm

An LSD is a limited-slip-differential.

A differential gear allows the two wheels on an axle to turn at different speeds. When cornering the outside wheel will have to turn faster than the inside wheel to describe a larger radius around a corner. In other words it has to cover a longer distance in the same space of time.

With a normal differential gear if you input more torque than there is grip available to handle that torque then the wheel with less grip will spin, reducing transmitted torque. An LSD apportions torque to both wheels and allows more of that torque to reach the road before wheelspin occurs. As the torque is applied to both driven wheels it also allows far more controllable slip, or drifting. If you see a rear wheel drive car spin both rear wheels then it has an LSD fitted.

Some E30s had LSDs fitted as stock, such as the is. LSDs are also available aftermarket from companies such as Quaife, whose ATB (automatic torque-biasing) diff is very popular. Off the top of my head I think they're around the Ԛ£600 mark.

I'm sure others will be able to provide more info on the different final drive ratios available.
1an
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Post Sat Nov 04, 2006 6:13 pm

allows you to be able to leave a proper 11 down the road. winkeye
Simon13
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Post Sat Nov 04, 2006 7:52 pm

i always thought LSD mean't Long Sildy Dildo no?
Chris-W
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Post Sat Nov 04, 2006 7:58 pm

Sildy?
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Simon13
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Post Sat Nov 04, 2006 8:00 pm

*cough slidy innit :o:

i'm such an illiterate fool
Chris-W
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Post Sat Nov 04, 2006 8:01 pm

I'm astonished there has been no lysergic acid reference yet. Oops, too late.
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Simon13
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Post Sat Nov 04, 2006 8:02 pm

answer the phone Chris RE shed?!
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Post Mon Nov 06, 2006 3:27 pm

lysergic acid dythalmide

"Flying for pocket money prices, tax that, Brown, you b*stard!!!"