[tomtom]

I took the plunge and went with the LSD. This transforms the car to new beast. Car no longer squirms like one tires is going to break free.

The car just hooks up so much better on straights and coming out of corners.
And of course...el driftos! are fun...but relearning the car now. so taking it easy.Car is so much more fun to drive.

Install went great! Thanks to Rocco at RMP! Those guys are fast and have great prices. In and out in no time. I plan to bring all my work...brakes, tires, suspension (M3 parts coming).

[Soni]

Originally Posted by tomtom

I took the plunge and went with the LSD. This transforms the car to new beast. Car no longer squirms like one tires is going to break free.

The car just hooks up so much better on straights and coming out of corners.
And of course...el driftos! are fun...but relearning the car now. so taking it easy.Car is so much more fun to drive.

Install went great! Thanks to Rocco at RMP! Those guys are fast and have great prices. In and out in no time. I plan to bring all my work...brakes, tires, suspension (M3 parts coming).

how much total cost you parts and labor?

[tomtom]

contact Rocco for labour cost...he'll give you the best price. just tell him I sent you.
the LSD is on sale now from Harold at HP. either you buy it for $1450 or whole final drive unit I think is $2700 with core returned, which is an much easier install.

[tomtom]

Soni,

these were going for $1650 USD and $3900 USD...they are all on sale.
the LSD is going for $1450 US, so $1800 CAD Shipped + taxes here.
labor for this install is 6-7hours. you are looking at about approx $3000 CAD installed. downside to this is that labor to remove latter will make buying the FD unit a better option.

Quaife final drive unit is $3300 but if you send your pumpkin, the cost is $2700 US. so $3250 CAD + taxes
This is a much easier install 2 hours.
so total for Final drive installed is $3900.
but you may want to keep your core, to put back in at a latter date.

let me tell you this mod is totally worth it. no more peg leg and one wheel burn outs!

here is more details:
"The Quaife Automatic Torque Biasing Helical LSD Differential enables a car to accelerate more rapidly and corner faster. How?

Simply by getting the power to the ground.

With an normal open differential, fitted as standard on most cars, much precious power is wasted through wheel spin under acceleration. This happens because the open differential shifts power to the wheel with less grip - along the path of least resistance.

The Quaife differential, however, does just the opposite. It senses which wheel has the better grip, and automatically biases the power to that wheel. It does this smoothly and constantly, and without ever completely removing power from the other wheel.

In cornering, while accelerating out of a turn, the unit biases greater power to the outside wheel, reducing inside-wheel spin. This allows the driver to begin accelerating earlier, exiting the corner at a higher speed.

The Quaife differential also controls loss of traction when the drive wheels are on slippery surfaces such as ice and snow or mud, providing the appropriate biased traction needed to overcome these adverse conditions. Power is transferred automatically without the use of normal friction pads or plates seen in other limited-slip designs.

The Quaife ATB Helical LSD differential's unique design offers maximum traction, improves handling and steering, and puts the power where it is needed most. A definite advantage, whether on the track or on the street.

The Quaife differential is extremely strong and durable, and since it is gear-operated, it has no plates or clutches that can wear out and need costly and regular replacement. There is no maintenance required to the unit, so you can fit and forget.

The Quaife differential is great for street driving or racing. Racers don't have to put up with locking mechanisms or spools that tear the steering wheel out of their hands when cornering. Because it behaves like an open differential during ordinary driving, street drivers will have trouble telling it's there until pushing the cars towards its limits.

The Quaife differential is proven in everything from SCCA Rallying to drag racing and Formula 1. It provides autocrossers with such an advantage, it has become "required" equipment for a winning effort.


Oh, I still have to take some pictures of your CF wrap. I get a lot of compliments. This is a great cheap alternative that looks really expensive. Thanks again for hooking me up!

[mikev333]

Does the current M3 have LSD? Because from BMW's website they call it variable M differential lock. Which one is better?

http://www.canadiandriver.com/articles/jk/at_011219.htm

The variable M differential lock.
A little extra traction can make all the difference, and the torque-sensitive, variable M differential lock identifies exactly when traction is needed. Even when wheel grip varies enormously, such as on bends taken at high speed, road holding remains excellent as the locking power between the left and right rear wheels can be raised to 100%. Drivers who expect the most from their cars know what this feature delivers: it optimizes handling, improves safety and enhances the thrust provided by the BMW M3 Coupé's rear-wheel drive.

[tomtom]

The ZF LSD is what BMW used all the way up to the M3 E36. It works, but has a couple of major downsides. Firstly, it has wearing clutches, which are costly to replace. The second problem occurs during the aforementioned pulling away from a wet junction. The way this diff transfers torque to a spinning wheel can only be described as sudden.

The differential actually locks up, effectively removing all the action of the differential. In this situation, the sharp transfer of torque is often
enough to break traction on both wheels. Entry speed into the desired lane of traffic is somewhat improved, but at a heroic angle of attack, and with plenty of corrective steering angle. This diff can be purchased and modified to fit many BMW open differentials. The torque split varies (instantaneously!) Between approx. 5% -25% or more. (Tuners like 10-40%) You can't do this with an open diff!

The BMW M Differential is great, but given BMW own it, it cannot be sourced from anyone but them, and at some substantial cost. It is capable of being installed into non-M models, but is expensive to engineer onto other cars. It uses clutches plus a viscous coupling to generate the reduction of slip. It generates quite a lot of heat while it slips, and is wasteful of power therefore. The Quaife ATB differential has to be the favourite.

It has no clutches to wear out, has a lifetime warranty, and gently massages the torque away from the spinning wheel to the one with more traction and is capable of varying the torque split between 0 to 80%. Perfect! It is genuinely one of the very best tuning products we have ever encountered in our 30+years in the BMW tuning industry.

No wonder Autocar said "As car addicts, we cannot allow the Quaife ATB to be ignored" And the result is?The little yellow flashing light is encouraged not to, and the car accelerates to it's maximum potential, with total stability. The driver now has the option to use all of the power the engine can generate. It's difficult and expensive to tune current BMW engines for more power. It's even harder to convert that power to acceleration. Rest assured, the Quaife ATB Differential is an amazing solution, without compromise.

[mikev333]

wow! thanks for taking the time explaining it. Now I have a better appreciation of LSD.

Lets track your car and let everyone take it for a sprin

[DaFish]

Great write up - thanks.

I have read some comparos between the Wavetrac compared with the Quaife.

Wavetrac has a zero load feature if a wheel comes off the ground it transfers the load to the other wheel, apparently Quaife can't do that.

Would both of these LSDs be very, very dependable and ZERO maintenance?

Anybody know what is better? Wavetrac or Quaife?

Recommendations?

[Kriston]

Great to hear you had a good success with the LSD. I would love to take a ride in your car one day to see the difference my self...

[Belarus]

Originally Posted by DaFish

Great write up - thanks.

I have read some comparos between the Wavetrac compared with the Quaife.

Wavetrac has a zero load feature if a wheel comes off the ground it transfers the load to the other wheel, apparently Quaife can't do that.

Would both of these LSDs be very, very dependable and ZERO maintenance?

Anybody know what is better? Wavetrac or Quaife?

Recommendations?

http://www.e90post.com/forums/showthread.php?t=358411

http://www.e90post.com/forums/showthread.php?t=359008