Cloudspin

This may be old news but I wasn't aware of it until today. Guard Transmission's clutch type, rebuildable LSD that I have seen advertised in Panorama and Excellence as being for 991s and 981s, works just fine on 997.2s with PDK as well. They can be purchased through BGB Motorsports (teambgb.com).

The short life of the factory LSD has been well documented on multiple RL forums as have the advantages of clutch type, rebuildable LSDs, most particularly for track use. I don't have the technical expertise to describe those advantages here but other RLers do.

I have no association with GT or BGB and just learned of this today on the Racing & DE forum.

Cheers.

tomc66

I have no idea what a LSD is.

Cloudspin

Limited slip differential. See pages 1 - 5 at http://auto.howstuffworks.com/differential1.htm from How Stuff Works for a better description of diffs in general and the differences between open / locked / limited slip diffs.

The second link is to the European Car Magazine website at http://www.europeancarweb.com/projec...x/viewall.html. It discusses the weakness of the factory LSD for track use on a GT3 project car and their reasons for (and the advantages of) changing to an aftermarket LSD.

I'm excited about it because the rear end of mine began slewing under heavy braking after my first few track days at Sebring. Especially into T7. It was initially much more stable in that situation than my 996 but became less and less stable with each additional day. I knew mine had the factory LSD which should have kept that from happening. I did a search on RL and learned that the factory unit isn't robust enough for track duty.

Hope this helps!

Cloudspin

Also, see the part in My Cousin Vinnie when Marisa Tomei is on the witness stand near the end. Much better looking than the guy on How Stuff Works and just as informative.

Kero

what is the cost of doing this? I have a 6spd but would be interested in having it done

chris.hanle

Tom66 might know what a "limited slip differential" is, but didnt know what you meant with "LSD". There are many things abbreviated with LSD. BTW I was in the same boat as Tom66 and I know what a limited slip differential is.

Cloudspin

^^
I know what you mean - I was around in the late 60's!
I'm a two finger (have 10, use 2) typist and a bad one at that so I use abbreviations too much to effectively communicate a lot of times.

Cloudspin

I think there more options for MT cars so you may not be limited to Guard Transmission. They are spoken of very highly though on the GT2/GT3 and Racing & Driver Educations. Matt is a regular on those forums - his RL user name is GTgears. Here's the link to their contact webpage which includes their dealer list:
http://www.guardtransmissionllc.com/

The pricing I got from BGB was for PDK only. Good luck!