LSD buster
10-05-2010, 11:30 PM
#77
Rennlist Member
Probably stupid question because I don't know much about this stuff, but what is the basic difference between stock LSD, CUP LSD and Guard LSD?
I usually think that if it works on a CUP car, it will work for me, but that's not based on any knowledge!
I usually think that if it works on a CUP car, it will work for me, but that's not based on any knowledge!
10-05-2010, 11:43 PM
#79
Rennlist Member
10-06-2010, 12:02 AM
#81
Rennlist Member
Read all posts above from "GT Gears"
Porsche LSD = Crap
New Porsche Cup LSD = Crap
Old Porsche = Pretty good gears but ****ty LSD
Porsche LSD = Crap
New Porsche Cup LSD = Crap
Old Porsche = Pretty good gears but ****ty LSD
I've seen all the posts from Matt, the man has the patience of a saint. if I'm spending money it will be there.
He probably answered everything I ever want to know 3x, I just don't know what he means.
So, you don't just change LSD "stuff" but also gears. Old 996 Porsche CUP stuff/gears fits?
10-06-2010, 12:15 AM
#82
Nordschleife Master
PS- Johannes van Overbeek gave us a one hour chalk talk a few weeks back and I was amazed how often "lock the diff" and "get the diff locked" came out of his mouth as he described his technique to get around Laguna Seca. A fully functional and properly ramped LSD is critical for track rats!
I am just disappointed that they didn't cover it more in the recent Excellence article about 600 miles with Patrick Long. I think a few of the things the author attributed to PSM and electronic gizmos were actually indications of the LSD (in the PDK Cayman in particular) not functioning properly.
I also wouldn't call the current factory Cup Car LSD "crap". They've got a billet body now. They've got 8 very functional (if quick wearing) plates in them. The ramp angles are pretty good. The only thing that's not so good about them is the cast gears.
Thank you to everyone for the compliments. I try and when I hear how happy our customers are, it's all worth it. I know that you all are all over North America, but any of you who will be at Sears Point on Friday I will be there just hanging out at the Porsche DE/Races. I can't stay through the whole weekend, but I did extend a business trip out there (and some super secret testing that I will be able to discuss later) just so I could go to Sears Point on Friday. I haven't been back there since I left Berkeley in 2001 and it will be nice to go "home" even if it's just to stand around in the paddocks for a few hours.
Regards,
Matt Monson
10-06-2010, 12:17 AM
#83
Nordschleife Master
Unfortunately nope, it won't fit. The GT3 uses a Getrag gearbox. The 997 C2 uses an Aisin Japanese gearbox. Just sell that GT3 LSD to someone with a 996 or 993, and put it towards buying one for the 997.
10-06-2010, 12:23 AM
#84
Rennlist Member
Thank you Matt. Always lurking in the background (on weekdays) ready to assist and point us in the right direction 
That quote caught my eye in that article, plus all re-reading all the posts makes me want to feel the difference from stock LSD. Originally I did not want to mess with my car for warranty, etc.
So, are 996 CUP LSD's stronger/better then 997 CUP LSD's?
Not sure if I have any choice, I'll go with whatever anyway, just interested.
“A lot of it is utilizing the differential to turn the car, where going to the throttle in a lot of the other cars could create understeer on exit. We can also trail-brake quite a bit, which has helped us overtake during the race…"
So, are 996 CUP LSD's stronger/better then 997 CUP LSD's?
Not sure if I have any choice, I'll go with whatever anyway, just interested.
10-06-2010, 12:30 AM
#85
Nordschleife Master
It's a toss up, and will also depend on what generation. Early 996 Cup still had cut gears. Late 996 Cup got the cast gears that are in 997. But all 996 Cup LSDs have the cast body. Early 996 Cup is 4 plate. Late 996 Cup is 8 plate.
997 Cup gets the billet housing but the cast gears. They are 8 plate.
There's some difference to the ramp angles between 996 and 997 but probably not enough to worry about. Either one will be better than the 28/40 of a 997 GT3 street car.
The important thing is that if they put in a complete Cup Car LSD or even just Cup Car friction discs, your LSD will work again.
997 Cup gets the billet housing but the cast gears. They are 8 plate.
There's some difference to the ramp angles between 996 and 997 but probably not enough to worry about. Either one will be better than the 28/40 of a 997 GT3 street car.
The important thing is that if they put in a complete Cup Car LSD or even just Cup Car friction discs, your LSD will work again.
10-06-2010, 01:51 AM
#87
GT3 player par excellence
Lifetime Rennlist
Member
Lifetime Rennlist
Member
It's a toss up, and will also depend on what generation. Early 996 Cup still had cut gears. Late 996 Cup got the cast gears that are in 997. But all 996 Cup LSDs have the cast body. Early 996 Cup is 4 plate. Late 996 Cup is 8 plate.
997 Cup gets the billet housing but the cast gears. They are 8 plate.
There's some difference to the ramp angles between 996 and 997 but probably not enough to worry about. Either one will be better than the 28/40 of a 997 GT3 street car.
The important thing is that if they put in a complete Cup Car LSD or even just Cup Car friction discs, your LSD will work again.
997 Cup gets the billet housing but the cast gears. They are 8 plate.
There's some difference to the ramp angles between 996 and 997 but probably not enough to worry about. Either one will be better than the 28/40 of a 997 GT3 street car.
The important thing is that if they put in a complete Cup Car LSD or even just Cup Car friction discs, your LSD will work again.
is "friction disks" aka "clutch pack"?
10-06-2010, 10:22 AM
#88
Nordschleife Master
Pretty much. The whole clutch pack is composed of friction discs, plain plates, and belleville washers. In most of our LSDs that's 10 pieces (5 per side). On the Cup Car it's 18 pieces (9 per side).
10-06-2010, 10:57 AM
#89
. . . Thank you to everyone for the compliments. I try and when I hear how happy our customers are, it's all worth it. I know that you all are all over North America, but any of you who will be at Sears Point on Friday I will be there just hanging out at the Porsche DE/Races. I can't stay through the whole weekend, but I did extend a business trip out there (and some super secret testing that I will be able to discuss later) just so I could go to Sears Point on Friday. I haven't been back there since I left Berkeley in 2001 and it will be nice to go "home" even if it's just to stand around in the paddocks for a few hours.
Regards,
Matt Monson
Regards,
Matt Monson
-Doug
10-06-2010, 11:17 AM
#90
Race Director
Matt, anything for 2009 997S with PDK? My car came with a factory LSD which from what I've read is either worn out or hardly ever used...I get confused about what to think. I took my car to my dealer a few months ago and had them check the LSD and they said it is working to spec....hummm I'm not exactly sure my Porsche dealer know what a LSD really is. LOL