Does a LSD increase liklihood of lift off oversteer in fwd car

Thomas. PLease. · 18 May 2009 at 22:33

Thread title pretty much says it all. I'm contemplating the idea of replacing the diff in my car with a quaife torque biasing lsd. And was wondering whether the chances of lift off oversteer are increased.

I know when you are cornering normally, you begin to understeer, you lift off, the weight shifts forward, the front wheels grip, and the back goes light and starts to oversteer. ok.

So in a car with an lsd, the understeer is vastly reduced, but surely the increased cornering speed, means that should you lift off mid corner, the liklihood of lift off oversteer is much more likely?

anyone know? just wondering?

Thomas.

merlin · 18 May 2009 at 22:35

Thomas. PLease. said:
means that should you lift off mid corner, the liklihood of lift off oversteer is much more likely?

Correct.

Clarkey · 18 May 2009 at 22:36

only with a 2 way. A 1.5 way will lock up to some extent on decel but shouldn't make the car too lairy, will just enhance control.

Thomas. PLease. · 18 May 2009 at 22:52

ok thanks guys.

Muffin` · 18 May 2009 at 22:53

how much does it look like it's gonna cost?

TaKeN · 18 May 2009 at 23:01

Surely the cost of that outweighs the benefits? unless your running silly power over standard

Thomas. PLease. · 18 May 2009 at 23:01

The LSD from quaife costs £550, which includes fitting to the crownwheel. Then I would probably get new synchro's and bearings on the box itself while its apart which would be another £120.

I'm just toying with ideas at the moment, partly because i don't want to risk another standard diff going bang as they like to. And partly as it would make the car even more awesome to drive. :cool:

Its not really about cost, I know its expensive, but I don't plan on getting rid of the car for a long long time. More money wil be being thrown at it soon to get it in perfect condition for track as well.

Dogbreath · 19 May 2009 at 08:51

Thomas. PLease. said:
So in a car with an lsd, the understeer is vastly reduced,

Not true. An LSD is primarily a traction aid, not a handling one. It increases cornering speeds only when it was otherwise limited by the inside wheel losing traction.

Housey · 19 May 2009 at 09:06

Not really convinced you'd notice that much difference on lift off oversteer with an LSD fitted as it's not going to improve your corner entry to apex speed really more your ability to put the power down coming out of the croner at which point power off oversteer is less likely anyway.

Thomas. PLease. · 19 May 2009 at 10:27

Right ok, I see now. For some reason i had it in my head that it would improve entry to apex speeds. So in reality it shouldn't increase the chances of oversteer at all. As by the time i'm putting the power down, I shouldn't be lifting off again. And as it won't increase entry to apex speed, it'll be pretty much the same as before.

Also I was wondering it would possibly help with oversteer recovery though wouldn't it. As if you get a really big oversteer moment, and need to throttle it to pull the car out, the increased traction would help that a lot?

Thanks guys.