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[mjohnson]

I actually have considered it.  I've also considered picking up some super cheap wheels for the front and slapping on some drag radials..

In my quest for an LSD I've noticed regular LSD's and torque biasing LSD's.  Is there a difference? or just a different name for the same thing?

[Smokestack]

I actually have considered it.  I've also considered picking up some super cheap wheels for the front and slapping on some drag radials..

In my quest for an LSD I've noticed regular LSD's and torque biasing LSD's.  Is there a difference? or just a different name for the same thing?

There's two types of LSDs, but I think the VW scene uses primarily torsion diffs (torque biasing). You have ones that use clutch packs on the side gears to limit the amount of different wheel movement. Those are typically dirt cheap and found in a lot of RWD cars and 4x4s, but the clutches are a wear item that need to be replaced somewhat frequently to keep the diff from becoming an open diff. Torsion diffs use a whole bunch of gears to transfer the load across the side gears.

Clutch type diff on right with an arrow pointing to the clutches. Open diff on left:


Torsion diff:

[mjohnson]

Good to know.

The torsion diff pic didn't wouldn't load.

[ianacole]

The big thing to consider when looking at a TBD vs. and LSD is the expected use.  A TBD is also a torque multiplier, multiplying the applied torque of the freer spinning wheel to the one with traction:

The Torsen (from Torque Sensing) works as an open differential when the amount of torque going to each wheel is equal. As soon as one wheel starts to lose traction, the difference in torque causes the gears in the Torsen differential to bind together. The design of the gears in the differential determines the torque bias ratio. For instance, if a particular Torsen differential is designed with a 5:1 bias ratio, it is capable of applying up to five times more torque to the wheel that has good traction.

The downside of this is that if one wheel has zero traction (ice, or in the air after bouncing off a curb on a race track, which is why I'm switching to an LSD), and your TBD is a 5:1 multiplier, 5x0 is 0, so it's back to being an open diff.  In most cases, the wheel with less traction, still has some, generating torque.  So if your inside wheel has 25% of the traction of the outside wheel, with the 5:1 TBD, 2.5 times the torque is applied to the outside wheel (very good at pulling you through a corner).

While an LSD does not have the benefits of multiplication, it will apply power to the wheel with traction regardless of the state of the wheel with less (or zero) traction.  This is why the LSD is a popular choice for race cars and 4x4 vehicles, which will see a wheel in the air at some point in time.  The downside of the LSD, as pointed out, is that it uses wear items to transfer power, requiring periodic maintenance.

For Volkswagen (especially the MKIV) most available differentials are TBD - Peloquin and Quaiff - with the WaveTrac being a "hybrid."  Kaaz has recently released a true, clutch-based LSD for the MKIV, which I am in the process of installing in our 02J, switching from the Peloquin.  While I won't have any direct reference for performance (back to back testing), I can relay some of my feelings on the performance and differences following this upcoming weekend's event at PPIR.

[mjohnson]

Good info.

[punkrider99]

It peaks at about 23 or 24psi at around 3300 I'd have to guess (without going for a drive right now).

now take that info and go look at your dyno plot and you'll understand why i said you're running lean.

[MileHighAssassin]

I kind of skimmed this but I wouldn't run meth injection over 40% meth.