flsupraguy

Has anyone been able to add a limited slip dif to a base 991.2?

John Mclane

I was told that heat dissipation becomes an issue. I didn't go further in the investigation due to expected costs

flsupraguy

hmm weird. I don't see how heat is an issue when the same exact thing is offered on a s?

flsupraguy

I emailed Guard, Quaife, and Sharkwerks. Will keep other base 991.2 owners up to date

LavaGTS

Is this why I couldn't do donuts in a base rental?

RobC4sX51

flsupraguy

Ok thanks. Emailed them too

spdracerut

Yup, OS Giken is well known in the track day community. They make pretty much the best diffs for S2000s, Evos, etc.

flsupraguy

Just an update guard said they have a LSD and it would be $3095 plus shipping. Seems reasonable? I wonder how much a shop would charge to install?

silveiradiogo

Hi, this is my first post so I will introduce myself:

My name is Diogo, I`m from Brazil and I recently ordered a Carrera T that is scheduled to be delivered in July. This will be my first Porsche.

I know it sounds like a sacrilege, but my spec is with PDK. Although I love manual transmissions, my choice for PDK was because it is faster in the track, that`s all. Unfortunately, I`ve discovered, after placing the order and the frozen date, that, when with the PDK, the Carrera T doesn`t come with the LSD or PTV+. In this case I`m looking for a LSD to equip mine.

That been said, I`ve sent an e-mail to Guard, Quaife and OS Giken. Here is what they have answered me:

Guard:

“Hello,
We have had a Pdk lsd to fit the open gearbox for several years now. It’s just not on the website, which is a bit outdated. Our spring production schedule has been delayed because of some equipment issues over the winter, but we should have them back in stock in a couple months.”

Quaife:

“Hello Diogo,
Thank you very much for your enquiry;
We don’t manufacture any diffs specifically for a PDK transmission.
The following link will take you to all the Porsche ATB diffs we currently manufacture:

https://shop.quaife.co.uk/catalogsea...er=48&model=&q=

You can download all the technical drawings for each of the diffs to see if they will work in your application.
You will have to have the standard diff removed in order to check this.
If you have any further questions or I can be of any assistance in the future, please don't hesitate to contact me.”


OS Giken:

“Hello Diogo,
We currently do not have confirmed fitment for 2017+ PDK gearboxes. If the design has stayed the same as the older gen's then yes our unit will work.
PR152-HC - Porsche PDK Super Lock LSD`”

They have confirmed the following models for the LSD:

“PORSCHE 997 (Twin Turbo) Cayman PDK (09'-15') and 991 PDK”


So I`m a bit loss in this. It sound like Guard will be the best solution, but I couldn`t find one single 911.2 base Carrera with any LSD installed.

Do any of you know if the PDK and the diff sizes are the same from 991.1 models? Would they be the same as the 997 also? Or maybe even the 996?

Thank you!

catdog2

How many hours for install?

stout

Keep in mind that an LSD can—as noted above—take different forms, and that an LSD may require different chassis tuning to account for its impact on handling.

All things being equal, I'd prefer to have an LSD. Better traction on the way out of turns, with better stability on the way into them (depending on the LSD/setup). And the idea of a base Carrera with an LSD but without PTV is very interesting to me as a purely mechanical device. But...and this is a big but, if it means upsetting or messing with a chassis that I feel is among the best and sweetest from Porsche in the last 10-20 years, I am a lot less interested. I was also interested to learn that Bernd Kahnau (known at Porsche as "the 911 maker" responsible for 4-5 generations of the 911...993 to 991 I think) chose NOT to put an LSD in his "F22" 911 hot rod when I interviewed him. I asked him why, and he said it made the car easier to drive on the road. I think he said it felt lighter/sweeter, too. I'd have to go back to the interview transcript. Even so, I still think about an LSD in the base 991.2. Then gain, I have yet to slip an inside wheel...

The best guy—or one of them—to hear from on this subject would be Matt at GT Gears. Would be interesting to hear his thoughts on types of LSD and their effect on chassis setup if any.

John Mclane

https://www.************.com/content...ntial)-upgrade

go.illini

You would never slip an inside wheel unless you are driving with the PSM completely turned off. Automatic Brake Differential (part of PSM) would brake the wheel that loses traction.

stout

^ What I should have said was...

I have not noted PSM intervening to deal with inside rear wheel slip while my base Carrera leaves turns. That was a distinct problem in one modified 987.1 Cayman S with an open diff that I drove in a comparison test, to the point that I turned off PSM and simply managed the wheelsman manually—a sub-par situation that cost the car a win against a pair of modified 911s. With that said, the modern PSM (997 GT2 >) is so transparent in use that my 991.2's PSM light may well be flashing or illuminated while my eyes are looking ahead. But I kind of doubt it. If I am wrong, that makes an LSD very interesting. I'll (carefully) see if I can keep an eye on that PSM light a bit more closely. But, my take so far is that the base Carrera's weight over the rear tires + its relative lack of power mean this is not a big issue in CA street driving.