One can google to find out more about the LSD types, but here is already a start:
http://en.wikipedia.org/wiki/Limited-slip_differential

Now one of the reasons I prefer clutch type ones (for street the 1.5 way), is with their pre-load will lock the wheels on slippery roads (and pending the ramp angels will lock them quicker/later on non-slippery roads.) Also on the straights, if the wheels do spin, the go both together and will be very predictable behavior.

If money is no object, I can recommend the os giken TCD one.

The others where I have experience with are the ATB ones (Geared type in the link), as they multiply by a certain factor (iirc about 3 for most max) the force from a wheel with less grip, it will not work anymore if 1 wheel doesn’t have grip anymore (ie 0 x 3 = 0). Also the breakout will be less predictable again as 1 wheel could spin more contrary to the clutch ones.

The reason why I think the clutch types work better with DSC, is that DSC will react less quick/active when both wheels are spinning, instead of 1 (which can still happen with the gear types). Especially when you make a 90 degree turn onto a road, you can floor it with a clutch type unit (well almost), but with an open diff/ATB type, the difference in wheel speed will activate DSC much quicker again limiting how fast you can make the turn.


What I am not sure about is how quick DSC will work, and this is just theory, if with an atb type 1 wheel loses grip, the ATB moves part of the force to the other wheel which still has grip, so what happens if the DSC steps in as well, and tries to break the wheel so in effect creates a wheel now with more grip?

Or in other words, you might want to investigate which types are available that could fit into the stype, and then make a decision on which one you prefer best.

 

+1

That's the beauty of a clutch type LSD on RWD .. in all conditions. Once you get used to it of course. Great gobs of fun steering with the throttle

BTW, the problem with DSC is that it is completely out of the hands of the driver. The reactions to a given set of inputs was designed and set in some lab according to some set of parameters .. it has no allowance for the situation as seen immediately in front of the driver, nor does it allow for the skill of the driver. TRAC on a icy rutted secondary road at speed will wear you out in no time as you and the TRAC fight each other's corrections. Better to just turn it off in those conditions.

 

Over the years I've found that I Like Gleasman/Torsen LSDs the best.

T-2R (RaceMaster).

 

Eric (DTS) is out of his office for a week. Left a message on the offset nature of the Gen II carriers and again visit this thread. Still confident they'll be able to retrofit a Traction-Lok differential to the S-Type carrier.

 

TY MrDeBruce!
Do you have any idea what engineering decisions went into adding TC and omitting LSD?

 

HA! Now THAT is a pertinent question!

 

This reply to everyone who is interested in an LSD for an STR, X350 or 4.2L X150.

Right now there is a diff on eBay for $160, plus $75 for delivery in the US.

2004 2005 2006 2007 Jaguar XJ8 XJ8L Vanden Plas Rear Differential | eBay

If someone (in the US) can buy it & have the seller send it directly to DTS, maybe it'll cost $235 incl shipping, maybe even less if they accept a lower offer.

I for one will contribute $50 to help get this thing over to DTS so they can get us an answer once & for all.

Who else is in?

 

Honestly I have no idea. The S type was my first project but I started on it on 2004 with the intro of the diesel. However I suspect it was a combination of money, specifically the tooling and D&D cost of developing one vs the attribute benefit. The S Type R was developed primarily as a long distance gentleman's cruiser so it was probably felt that the benefit of the LSD was smaller than spending the money on other benefits, e.g. the Dynamic Suspension.

 

I will match your $50.

 

OH ... This exactly what I was hoping you DID know because let's face it, in addition to better overall traction (actual delivery of power to the road) I think most of us are hoping that the traction control the car has now will be far less likely to engage.

Of course you can turn that off but I wouldn't want to do that in most street driving situations.

I guess we'll have wait and see how it does.

 

If this diff. matches the S-Type, then I'm also in for $50. Obviously, if a bunch of us are in then it could turn out to be $25 or less? One of us can buy out the rest for the test differential.

 

It's the same diff

 

Consider me in as well! Sounds like a great way to get this concept off the thread and into a working STR!!

 

Guys, does it make a difference whether its a V8 car of V6 car? Are the pumpkins the same for both?

If so I have found a few that would come in under $200 with shipping.

I have a long history with eBay been on there since 1999 buying and selling and I would be glad to purchase the diff and get it shippied up to DTS with some coordination from the group...

Let me know and I will get the ball rolling on acquiring the diff for us!

 

V6 diffs are same internals but different ratios, really should stick to the V8 diffs with 2.87:1 so someone can use it once it is put together.

 

Dang...

In that case how about this one?
Jaguar s Type V8 4 2 4 2L Rear End Differential Carrier 03 07 2 87 Gear Ratio | eBay

 

Link won't open on my stupid iFone but from the description it sounds ok

 

Says this:

Came from:
2003 Jaguar S-Type R (V8 Supercharged)
Vin #M66602, 60K Miles

2.87 GEAR RATIO.GREAT SHAPE, ONLY 60K MILES.

 

That's it. Are we in? Let's get this rolling.

 

Buy it, pm us an email address to paypal the money