Yes it does, but it's also a more expensive and less durable approach than rebuilding one with our internals. However, for the 996TT guys they don't have a stock LSD available to them to start with. The first they've got to do if they want to take that approach is go out and buy a stock LSD, which we all know is a doorstop until someone goes through it and puts some decent clutches in there...

 

I'm pretty sure no US cars come with an LSD. Someone said a while back that an LSD was an option in Europe so some of their cars might have them.

 

I was pretty sure that at least from the 996 onward, there was not even an option for LSD in any AWD 911. You saying the option did exist? that would be very interesting as it throws a totally different dynamic into the car based on this entire discussion.

As an aside to all who get a porsche LSD: Last year I purchased a basically new GT2 LSD. Both myself and the seller thought it was a good deal. I have been working on install for the last 3 weeks. And this is what I have learned. In order to do it right, you either have to remove the trans to properly shim it or you have to reuse the old bearings and races. Then you do not have to remove it. But here is the kicker, the 996tt diff flanges do not fit the GT2 diff, so I now have to buy dif flanges at a whopping $1k, which makes this good deal not so good a deal anymore. I could have gotten a guard for the same price. In any case, this is just a word of caution. If you find a used GT2/GT3 LSD make sure you have the flanges come with it.

 

I don't know for sure, I know I read that on here somewhere, but can't remember where. I have no way to confirm it though.

That sucks about flanges for 1k!!!! Can you find someone to make you some so you don't have to pay the Porsche tax? My OS giken diff required some type of shims or something but Eric from Gbox walked my mechanic through it so I have no idea what he did.

 

I probably could have found someone or some used ones, but my car would be sitting even longer and I am getting itchy to drive.

Here is another update on the flanges: From 2004 on the Turbo diff flanges and the GT2 diff flanges were the same....HC, maybe it was this year that LSD became an option since it is a direct fit, no flange issue. I will ask my porsche mechanic friends, they should know.

 

Some versions of the 996TT use the same clip-in stub axle flanges found on the 996 Carreras. All of the factory and aftermarket LSDs are intended for use with bolt-in flanges.

There's two common ways to resolve the issue. The first is to replace them with ANY G50 or GT3/GT3/997TT flange. A flange from a 1987 through 1998 air cooled 911 will work. As will later flanges from the above mentioned vehicles. Usually these parts can be acquired used for around $300 a side or several vendors make them and sell billet upgraded versions for around $450 a side.

The other option, and what was likely done on Heavy's installation, is to take the end of the circlip flange and cut it off. You remove just under 10mm of material to make it the same length as the above axles. Then you through drill it so that it can accept the standard stub axle bolt and attach to the differential.

 

People are misunderstanding the purpose of LSD vs. PSM. PSM (stability management) is useful on wet/snow/ice/gravel roads. It works by reducing power to the engine and pulsating the brakes for you to regain control of the vehicle. LSD locks power to the rear wheels or all four, not reducing power to the engine but allowing you to distribute the power equally to 2/4 wheels.

On 99-04 car PSM can not be shut off. Shutting it off only puts it in "sleep mode" pressing the brakes will reactivate PSM briefly.

Per http://en.wikipedia.org/wiki/Porsche_911

"Starting from the models with water-cooled engines, 911 Carrera's do not come with rear limited-slip differential, except the 40th Anniversary 911, GT2, GT3 and Turbo."

 

[QUOTE=stephan_porsche;3568103]
On 99-04 car PSM can not be shut off. Shutting it off only puts it in "sleep mode" pressing the brakes will reactivate PSM briefly.
QUOTE]

Can't you turn if off by unplugging it

 

Guys...

You must do these 3 steps:

- Unplug the PSM
- Install LSD
- Enjoy great driveability and great lap times!

No matter whether it's AWD or RWD 996 Turbo.

 

I'll take PSM that comes on when the brakes are pressed any day. I know I want to be professional driver, but sometimes anyone can overcook it, or come around a corner and hit water or gravel... It's comforting to know it's there

If I would add that feature to my 6GT2 if I could. But it seems it's it's not just a flash thing

 

What type of LSD is Ruf using these days in their new builds?

 

when you disconnect that plug you also lose ABS I am told by my shop ?

 

For the past few years since Porsche introduced a billet body on the Cup Car RSR LSD they've been using Porsche Motorsports units. Prior to that, they used ours.

 

Your shop is wrong. When you disconnect the connector to the precharge pump you disconnect PSM and retain ABS

 

Great I know what I am doing today