I'm a bit clueless when it comes to cars , anyone mind telling me what benefits does one get from a LSD in a C2 ? and what disadvantages that come with it as well .

 

more traction, which means better handling, better launches etc.
less tire hop

 

Briefly:
Most cars have open differentials this means then when one wheel has no contact with ground or limited contact it will spin at high speed and the wheel that is in contact with the ground will remain stationary (if the car is not moving). The standard 997 diff is open. In all cases the torque sent to each wheel will be equal and will not exceed the minimum torque required to rotate the wheel that is not in contact with the ground. i.e., if the car is stationary it will remain so and if moving it will slow down.

When driving around corners the inside wheel becomes unweighted and can break loose, when this happens the torque applied to both wheels is simultaneously reduced resulting in less performance in the curves, not a problem in normal driving, but on a track it will lower your lap time (provided the driver can extract that bit of performance out of the car), during straight line take offs if one wheel has less grip it will adversely affect the acceleration (but so will limited traction), probably not a problem unless you drop the clutch at high revs.

LSDs limit the difference in angular velocity between pairs of driven wheels, so that torque is transmitted as long as there is some friction available on at least one of the wheels, eliminating or reducing the above problem. In other words they limit the slip and apply torque to the non spinning wheel in excess of the torque applied to the spinning wheel.

There are various ways to manage this based on torque (e.g., Quaife), clutch based, viscous coupling, electronic (basically using the ABS to limit slip of the spinning wheel, they all have there pros and cons.

My opinion “unless you track your car don’t bother” but I understand the need some folks have to own and drive the ultimate machine, so have fun spending your money.

 

If ordering an 09 my advice is to get the LSD . There are many discussions of whether it can be retrofitted and it can but it costs a lot more to add it than to have it from day one .

Any peformance option geared towards better traction and handling can not be detrimental . Many may never use it and if one falls in love with a car on the lot which does not have it I still would say buy the car .

Porsche did not include it on many of the street cars . The Gt3 and Gt2 have it standard . Even the AWD Turbo has it as an option and all tiptronics to this point do not have it .

Porsche finally has recognized that many buyers want to track the cars or simply have thie perfomance feature and my feeling about cost saving is skip the carbon fiber, skip the navigation, skip the deviated stitiching --but NEVER skip performance .

BTW -- My other cars -- both the 07 Civic Si and 08 BMW M3 --BOTH vae LSD . Now its true that a front engine car may need it more but IMO there is no excuse why Porsche didn't place this feature in ALL the cars .

 

can it be retrofitted in a 06 c2s?

 

LSD is in the gearbox.

 

LSDs have pros and cons. They will help in one very limited circumstance - on the track to prevent spinning the inside rear wheel when accelerating out of tight (usually 2nd gear) corners. On the street, they won't help any (whether it may make a difference on a clutch-dropping launch, I don't know - could help or hurt).

Cons? LSDs tend to introduce more understeer when turning in to a corner. Again, you probably won't notice this on the street.

Conclusion - street driving - a total waste of money. Track driving - if you are really going to push it hard, it will be of some benefit.

 

As mattwhitte said "Conclusion - street driving - a total waste of money. Track driving - if you are really going to push it hard, it will be of some benefit." and as I said earlier "My opinion “unless you track your car don’t bother” but I understand the need some folks have to own and drive the ultimate machine, so have fun spending your money."

It can be retrofitted - I don't no how long it would take but you can start here:

http://www.quaife.co.uk/

They have distributors all over the world.

 

I had 3 LSDs (AWD vehicle) installed on my '96 Eclipse GSX from Road Race Engineering when they used to be in Huntington Beach. It was purely for 1/4 mile track. I agree with Matt and MartinJF...total waste of money for street driving. Besides what was already stated from others here, you know the rules, once you start taking things apart and modifying them, make sure your bank account is nice and fat as this starter project only leads to reinforcements, more modifications to support said project, etc, etc....
But hey, its your car. If you feel you need it go for it. You are going to do it anyway.
Cheers.

 

Matt -

The LSD in the 997tt is touted as the "must have" option even though that car is AWD because it CAN launch well and take those corners.

The same is true of the 997S and that's why the European 997S cars can have it as an option wheas the USA cars do not.

I will agree with you that while sitting in gridlock traffic or at 55 MPH on a highways LSD is useless but one might argue that so is a perfrmance car .

Resale WITH an LSD can improve a value -- but with a 997S one does not get a choice --UNTIL now .

Where one does see a choice is on the Turbo that's the best place to ask as the overwheming majority of 6speeders did get the option . Ask them why --some have driven BOTH cars (with and without) . Ask them aboit resale . Then ask yourself why is Porsche now giving it standard on ALL AWD cars and offering the option on the 997(s) cars.

The LSD which comes standard in my other cars which cost much less than my Turbo is a welcome feature .

 

In my experience on posting on various car/track message boards over the years, I can safely say that LSDs are the most misunderstood piece of performance equipment out there. Aside from launches (which make absolutely no difference to me), the sole issue in deciding whether to get an LSD should be "am I getting inside rear wheel spin when accelerating out of one or more corners." If the answer is no, then you don't need an LSD, period.

I have no idea about the Turbo - makes sense that it my benefit from a LSD for launch purposes. But I seriously doubt that many people are getting any cornering benefit on the street. Again, on the track, it's a whole different story.

The 997S is an entirely different animal - far less hp and torque. In my experience, I just can't see how anyone is ever going to need an LSD for street driving. And I'm not talking about going 55mph, I'm talking about driving as fast as you can without risking injury to yourself and others.

Additional considerations are the big downsides that comes with an LSD - the increase in understeer on initial turn in to corners and the increase in potential for snap oversteer if your slip angles become too great and you lose traction. I'm sure Porsche has done its best to deal with this, but I would not get the LSD until I knew how big of an issue this turns out to be.

Resale value: you very well may be right on this, but if you are, it will be because most people are misinformed regarding the benefits and downsides.

 

Hey guys. I got my LSD, a Quaife (very well-respected name) from Dan at Vivid. He's a sponsor, and is great. I'll be driving it on the track soon with it, and will let you know what I think for real.

 

Thanks for all the help guys