3 Reasons Why You Need A Quaife Limited Slip Diff...
#12
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Location: London
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My Ride: 2006 520d - 19" 172s- Remapped - LCI taillights V6 cables - LCI xenon headlights - Denison 500 with BTA1500 - led interior lights - OEM led number plate lights
Planned mods:
Folding mirrors - Modmynav kit - High gloss shadowline trim -
In simple terms (because I don't know what this is) what will this add to the car performance wise? Why not just stick to a remap?
#13
You can remap your car to 1,000 bhp, but the power will be going nowhere as your wheels will just spin.
An LSD simply puts your bhp on the road (what the open diff fails to do, particularly in wet/slippery conditions).
#14
#15
A LSD, and in this case a torque-sensing LSD, acts mechanically to eliminate wheelspin, assisting the DTC system (in most cases eliminating its need to intervene), and reducing the likelihood that the traction control system will actually have to cut engine power. There are advantages and disadvantages to the Quaife system versus clutch-type LSDs (with the biggest disadvantage being that if one wheel completely loses traction, it reverts to being an open differential), but in my opinion its advantages overwhelm any disadvantages, particularly because the DTC basically solves its primary disadvantage by providing resistance to a free-spinning wheel, preventing the open-diff scenario.
Note that mechanical LSDs were available from the factory on a lot of BMWs until a few years ago, and now are only available from the factory on M-cars (though they are very fancy clutch-types with hydraulics, etc., to control the amount of lock). Note that M-cars also have traction control systems, so it's not as if these things aren't designed to work together, or that the LSDs don't add something.
The other handling benefit they provide is that they make the car feel more alive, particularly in situations where you might be able to create some power oversteer. Rather than just have you just lose the inside rear wheel in spin/tire smoke when getting on the power coming out of a turn, you can more easily get the rear to step out a bit under power. Not that I'm advocating that of course.
They are also great in snow. My older BMW with a clutch-type LSD was great in the winter. You could just get the wheels spinning the car could get up almost any hill, while most lesser cars were spinning only one wheel and getting nowhere, my rear-end would lock up and both wheels would work to create forward motion. The car would take a set with the rear end to the left or the right depending on the crown of the road, and would just tractor its way up.
#16
JM, can you elaborate a bit on the "one wheel completely loses traction" scenario? I have read lots of opinions on the Quaife LSD, but this is something new to me.
Does this happen only when the wheel suddenly and completely loses traction, i.e. when you have parked the car with one wheel on really smooth ice?
Because under real-life driving circumstances one wheel will only gradually lose traction and the LSD will prevent it from continuing to do so (by taking torque off it).
And in the first case, does the DSC help at all if you are still at the same spot with one wheel on ice?
Does this happen only when the wheel suddenly and completely loses traction, i.e. when you have parked the car with one wheel on really smooth ice?
Because under real-life driving circumstances one wheel will only gradually lose traction and the LSD will prevent it from continuing to do so (by taking torque off it).
And in the first case, does the DSC help at all if you are still at the same spot with one wheel on ice?
#17
JM, can you elaborate a bit on the "one wheel completely loses traction" scenario? I have read lots of opinions on the Quaife LSD, but this is something new to me.
Does this happen only when the wheel suddenly and completely loses traction, i.e. when you have parked the car with one wheel on really smooth ice?
Because under real-life driving circumstances one wheel will only gradually lose traction and the LSD will prevent it from continuing to do so (by taking torque off it).
And in the first case, does the DSC help at all if you are still at the same spot with one wheel on ice?
Does this happen only when the wheel suddenly and completely loses traction, i.e. when you have parked the car with one wheel on really smooth ice?
Because under real-life driving circumstances one wheel will only gradually lose traction and the LSD will prevent it from continuing to do so (by taking torque off it).
And in the first case, does the DSC help at all if you are still at the same spot with one wheel on ice?
There are quite a few folks around here who have Quaifes installed, and I have only heard rave reviews. The DTC function is said to work seamlessly with the Quaife, and the Quaife can only be a traction benefit, even on ice.
#18
Senior Members
Absolutely: there is an entry, in the FSW_PSW, to tell the car you have the LSD.
So yes, the car was prepared for LSD.
And after 3.5 yrs with the Quaife installed, I confirm no problem with the DSC/DTC.
#19
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Model Year: 2015
Engine: N55
#20
We are in Santa Barbara, CA. The price is $1450 with free shipping to the 48 States(up to $35 value) and free stub axle seals(a $39 value).
If we can get 5 people together we can order a batch of these units. Then we can do $1305 with free shipping and stub axles. We can save each person an additional $145 on top of the free stub axle seals and shipping.
If we can get 5 people together we can order a batch of these units. Then we can do $1305 with free shipping and stub axles. We can save each person an additional $145 on top of the free stub axle seals and shipping.