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Old 07-16-2018, 03:05 PM   #17 (permalink)
Desert Rat
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Quote:
Originally Posted by JARblue View Post
Open diff keeps rear axles spinning at the same rotation (speed). Not good on a track when you're powering through a turn.

VLSD transfers some power from the inside wheel to the outside wheel in a turn. This effectively allows the wheels to rotate at different speeds to maximize traction and prevent slipping during a turn. Of course the VLSD isn't a proper track solution - the fluid overheats way too easily and it just turns into an open diff until it cools down.

A 1.5 or 2 way diff allows a lot more power transfer and is ideal for track driving.
Um, that's not how they work at all.

An open diff puts all power to the wheel with the least amount of traction if traction breaks loose. If one wheel breaks traction, no power goes to the other wheel.

An LSD enables some of the power to be split in that same situation, provided the needed breakaway torque to get power to the other wheel doesn't exceed the breakaway torque in the LSD. Clutch discs are used in the diff to provide that additional friction. Those clutch discs wear out over time and an LSD becomes more and more like an open diff. Nissan has always used minimal breakaway torque in their LSD units, greatly limiting their effectiveness. Same holds true for the old LSDs they used in D21 and D22 trucks. With those you could slide in 1-2 additional discs to "tighten up" the LSD, and with enough additions, you can basically turn an LSD into a spool where both wheels always get the same power. That's not desirable either because in a turn, that means the inside tire HAS to break traction to prevent binding.
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