MTR

I have a 964 Carrera 2 with a manual transmission and factory gearing. The car didn't come with the factory LSD option, so I'm thinking about adding one to improve putting the power down out of slow speed corners and more stability trail braking. Keep in mind the car is not a dedicated track car (~5-6 track days per year) and it still gets driven 2,500-3,000 miles per year on the street.

So the research I've done leads me to 3 options:

1. Used 4-plate OEM LSD with new plates. ~$1,500
2. OS Giken ~$1,900
3. Guards Clubsport/Pro - $2850-$3200

I know that the Guards is a proven unit, but I'm curious to hear feedback on the OS Giken or if anyone thinks the OEM unit is good enough for my application.

Thanks.

Slakker

Just got an OS Giken from Gbox in CO and they were great to deal with. The standard Giken config is great for track duty but Gbox can restack it a little less aggressively for street/track use if you choose.

Bill Verburg

There are numerous g50 lsd's that were oe, the best would have been a Motorsports GKN 40/65, after that one of the 993 GKN or ZF 25/65 modified w/ GT plates. The older unit used in '87-89 911 would be ok too but it is just a straight 40(though it could be set up as an 80)
As I understand it the 964 versions for the most part can't be upgraded w/ 4 GT plates except the 20/100 used in 964RS and 964t, but the lockup on that one isn't desirable for most users.

You won't need a GT Pro unit, the GT Club 40/60 would be more than sufficient for our cars.

MTR

Bill thanks for the insight. Do you have any experience with or talked to anyone who regularly tracked a Giken unit? Saving $1,000 is enticing.

MTR

Slakker - what car did your Giken go into? I assume you haven't had the chance to track it yet?

Bill Verburg

No experience and no opinion on the Gicken. Everyone I know has oe or Guard.

Back when I was setting my car up I had purchased a GT 40/60 but ended up buying a Porsche Motorsports g50/30 trans w/ GKN 40/65. Toyed w/ installing the GT in that but decided to stay w/ the oe PMS unit.

My street car w/ 915 has a ZF 40 w/ upgraded preload, it is far more intrusive than the PMS race unit.

linzman

I had an OS Giken in my 87 911, and it was great. Much better trailbraking, No more wiggle in the back end under hard braking, and no wheel spin out of slow corners. But mine was a dedicated track car, not sure how it would be for street driving.

HDA

I am in your same shoes. Would love to save $1,000...!

MTR

I still haven't made a decision on a LSD. A friend recently bought an OS Giken for his 964 so I was waiting on his feedback before pulling the trigger. So far he is happy with the unit so I'm leaning that direction.

Let me know which LSD you end up choosing. Do you plan on tracking your car or is this for improved traction on the street?

HDA

In regards to your friend, the fact is that if he had NO lsd before and he install one, even the OBX (maybe), he's going to tell you that he is happy!

I plan to mainly track (not race) the car. I wouldn't put an LSD if I didn't plan to track the car.

My goal is to get an LSD that won't disintegrate every 5000 miles and that provides 2 ways locking.

I am currently reading this post which I find entertaining / informative

https://rennlist.com/forums/porsche-...to-have-2.html

stujelly

guards

matt is a stand up guy and a rennlist sponsor

cant go wrong

MTR

No he had a Porsche OEM 2-plate that eventually failed so rather than rebuild a 2-plate he wanted to get something a little better and went with the OSG.

I've heard that from a few people. Cadrega want to get a group-buy together for the Guards Club LSD? I think they are $2850 now, maybe pick them up for $2,500 if we can get a few people to get in on it.

HDA

You've got a PM!
Although I don't know if the 2 of us can be considered a group buy

HDA

In the end I am leaning towards the guards too for 2 reasons:

- reliability. It is an expensive job to take a diff out. I want to put one in and be done with it. Foreva 'n eva
- resale. The fact that you put a guards LSD in your transmission is a "plus" for most buyers.

winders

Having seen an OS Giken that had grenaded, I would NEVER buy one. I would get a Guard LSD or a Porsche Factory LSD. But I would much prefer the Guard LSD.