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...so that technically means yes :D.....
But I also see that the website says in fine print above
"John Cooper Motorsport only supply Motorsport parts direct to MINI Markets around the world who run a MINI Challenge Race series. In addition, for bespoke Motorsport conversions John Cooper Motorsport parts are only available for supply and fitment at John Cooper Works in East Preston, UK. John Cooper Motorsport parts cannot be sold via the internet or mail order"

Err, does that mean the parts cannot be ordered? I am in America, and what if I want a JCW LSD?
 

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mcswrks said:
I am in America, and what if I want a JCW LSD?
Why don't you just get a Qualife? The JCW will most definitely be more expensive and no MINI dealership in the States will have ever installed one before. A Qualife can be installed by any reputable aftermarket shop that specializes in MINI's.
 

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Track Addict
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Hi,

The new spec cooper S can be specced with a LSD from the factory. It is quite a cheap option.

However, I believe this is not a "viscous" type LSD like the quaiffe.

Does anyone know if this new LSD can be rertofitted?

Cheers

Robbo
 

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Half a dent
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I have seen a number of posts and info from motoring file saying that the lsd cannot be retrofitted except by replacing the entire gearbox gubbins at a parts price of over £2000. Shame really because the mini can't cope in the wet/ice with 210bhp through the runflats
 

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cristo
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robbo mcs said:
Hi,

The new spec cooper S can be specced with a LSD from the factory. It is quite a cheap option.

However, I believe this is not a "viscous" type LSD like the quaiffe.

Does anyone know if this new LSD can be rertofitted?

Cheers

Robbo
The Quaife LSD's aren't a viscous type LSD...they use helical gears in a torsen
arrangement to route torque preferentially to the side with the most grip.
 

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6X therapist
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13,907 Posts
robbo mcs said:
Hi,

The new spec cooper S can be specced with a LSD from the factory. It is quite a cheap option.

However, I believe this is not a "viscous" type LSD like the quaiffe.

Does anyone know if this new LSD can be rertofitted?

Cheers

Robbo
Factory fit LSD is part of Chilli Pack and standard if you have chilli from Jan 05
 

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///M Power
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5,066 Posts
rentagas said:
I have seen a number of posts and info from motoring file saying that the lsd cannot be retrofitted except by replacing the entire gearbox gubbins at a parts price of over £2000. Shame really because the mini can't cope in the wet/ice with 210bhp through the runflats
I've been told that the oem mini LSD isn't actually a real LSD, although it is meant to perform very well... BBR do a quaiffe type LSD, for around £1200 fitted, which is still expensive, but a better option than trying to retrofit the oem version IMO.
 

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Southern Florida Coop S'
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Discussion Starter · #13 ·
OK OK, I am right!. not only can you configure your 05 mini coops with one JCW has one!

Well then on with my story, I blew the transmission in my 05 coop S. only reason i found this out is because they recalled it. while the transmission is dropped i want to install an LsD good idea?
 

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Best Personal Regards
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VERY GOOD IDEA. Get a Quaife either direct from the factory in the UK or from Taylor Engineering in the US or even MINI MANIA will sell you one. I would suggest MINI MANIA as they will also sort out the new bearings you will need (not available from MINI or BMW)
The change is VERY straight forward.
Been there, done that.....awesome difference in terms of road racing and slaloms.
 

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Quaiffe unit is torque biasing and is not a 'complete front lock up' like a plate diff.
It is the same unit as is fitted as std to Ford Focus RS. It is a halfway house between
std diff & plate type. Plate diff will corner quicker but you may crash getting to the corner! requires immense skill & bravery to get 100% out of it. The new OE optional LSD is not made by Quaiffe ,
Regards Roland Gt Tuning
 

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roland2003 said:
Quaiffe unit is torque biasing and is not a 'complete front lock up' like a plate diff.
It is the same unit as is fitted as std to Ford Focus RS. It is a halfway house between
std diff & plate type. Plate diff will corner quicker but you may crash getting to the corner! requires immense skill & bravery to get 100% out of it. The new OE optional LSD is not made by Quaiffe ,
Regards Roland Gt Tuning
Hmmm...

The whole reason I was reading this thread was to try to find out conclusively what design the 05 Mini LSD is, and it doesn't look like anyone has that info yet. I'll throw in my own LSD experience from other vehicles anyway.

First and foremost, to be able to steer a FWD car the front wheel speeds have to be able to vary side-to-side (true to a lesser extent of RWD as well, but...) A diff that tries to equalize wheel speed side-to-side like traditional friction (plate or cone clutch) limited-slips will basically take steering control away from the driver. They've been used in loose-surface rally cars, but on pavement you basically can't steer them, unless they're set up so 'loose' as to be of limited use.

There's stuff out there like the Haldex and Gerodisc and etc. that use either electronics and wheel-speed sensors or an hydraulic pump driven off the diff internals to engage the friction elements, the premise here being that the engagement can be smoother and less aggressive than with traditional friction types. The GKN Viscolok is a similar hydraulically-actuated design and given that press releases indicate that the Mini's diff is sourced from GKN and that BMW uses the Viscolok in the M3 it seems likely it's a Viscolok derivative, but I haven't seen anything conclusive.

The Ferguson-type viscous limited-slips as used in various Nissans and Euro Fords (and I think some Fiats, etc we have never gotten in the US) in past years work okay, they attempt to equalize wheel speed side-to-side but are 'soft' in doing so. Their biggest limitation is that that 'softness' makes them a little slow in acting and less than aggressive in limiting wheel spin. I've also heard that the silicone fluid in the diff tends to lose its resistance to shear over time.

The worm-gear torque-biasing diffs - Quaife, Torsen, Tochigi Fuji, DPI Gold Track/Black Gold, Tractech TrueTrac, etc - are completely different beasts. There's a couple different flavors, and I really can't explain in one sentence how they work (and I'd probably be wrong if I tried.) Fundamentally, they don't care about side-to-side variation in wheel speed at all, they measure the relative side-to-side resistance of the wheel to the torque being applied and are continually rebalancing the output to the side that offers greater resistance. They will quite happily spin one wheel faster than the other, and dependent on the internal gearing will permit relative torque biases of 2.5:1 up to somewhere around 6.5:1.

The worm-gear diffs have a couple enormous advantages and a couple significant disadvantages. The biggest single advantage is that in track use (or road use more aggressive than common sense permits) the torque-biasing tendency makes the car throttle-steerable in a way you otherwise never see in FWD cars.

In most cases, with open-diff FWD you have to take off so much front roll stiffness, or add in so much rear roll stiffness, to keep the inside tire on the ground that the car isn't very 'driveable' in turns. With a speed-limiting diff e.g. friction, viscous, Haldex, etc. this is moderated somewhat, and you (or the manufacturer) can go back to a more driveable (less tail-happy) chassis setup, but more power still means both front wheels pulling at the same speed so it's still fundamentally understeer-biased.

With a Quaife/Torsen the outer wheel (as long as it's not massively overloaded) will have more grip, will get more torque as throttle is added and will tend to 'pull' the nose of the car into the turn. It's a remarkable feeling; the first time you experience it, your shouts of joy will have the corner-workers wondering just what you're doing in the car.

Now for the downsides as I'm aware of them, which are highly application-dependent (note that none of what I'm saying here is based on Mini experience.)

In FWD applications this tendency to rebalance torque side-to-side without controlling wheel speed can make the steering feel a little 'darty' over uneven surfaces. Some would say a lot darty, but it seems to depend a lot on the car and the wheel offset/steering scrub radius. In my Taurus SHO it's noticeable but not bothersome (unless you nail the gas too hard at low speed with the wheel cranked around as one would when making an energetic U-turn, at which point the steering wheel tries to go zing! out of your hands all the way around to the stop and turn a 180 into a tight 360...so one simply does not do that.)

In a traditional Quaife/Torsen design if one wheel is lifted off the ground or ends up on a patch of ice or slush (or wet pine-needles-and-leaves mush, or other near-zero-mu surface) the diff will go 'open'. The four-wheelers who run Torsens and TrueTracs learn to ride the brakes to overcome this, and some designs intended for RWD race applications like the Torsen T-2R and Gold Track/Black Gold include friction elements to prevent this. Otherwise, whether it's a problem depends on how frequently you tend to lift a drive wheel off the ground.

And, finally, all the wiping friction in those diffs generate heat, and the more power your car has and the more work the diff does the more heat it will generate. This is pretty much a non-issue for road cars, but for anything decently powerful that sees significant track use it's worth knowing your transaxle lube temperature. My SHO (Quaife, ~280HP hopefully headed for 320HP) has a cooler and pump on the transaxle, and my full-time track-car Mustang (Gold Track, 380HP) will have one once it's back together.
 
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