LSD Recommendations
09-16-2011, 10:48 AM
#16
The rear end is making a lot of rattling noise when I turn right. Workshop inspected all the under carriage components and took out the drive shaft to inspect as well. Now it's down to LSD. LSD is out now but they have no way to be sure if it faulty. It is the most likely cause at this point.
Thanks for all the advises. The workshop is sourcing for a replacement LSD now. I have suggested Cup unit and see what they say. I would like to do Guard but it's inacessible to me
Thanks for all the advises. The workshop is sourcing for a replacement LSD now. I have suggested Cup unit and see what they say. I would like to do Guard but it's inacessible to me
09-16-2011, 11:33 AM
#17
Rennlist Member
I had my LSD rebuilt with Guard internals and the difference has been fantastic. 50 track days later I'm still happy
09-16-2011, 12:06 PM
#19
Addict
Rennlist Member
Rennlist Member
Matt at GT gear deal with customers all over the world. Unless you are located in a war zone Matt will be able to get the parts or LSD shipped to you. If you want to find a used Cup LSD in your local then that's a different story. Will not recommend Cup LSD for street cars - they can be noisy
09-16-2011, 12:18 PM
#20
Matt at GT gear deal with customers all over the world. Unless you are located in a war zone Matt will be able to get the parts or LSD shipped to you. If you want to find a used Cup LSD in your local then that's a different story. Will not recommend Cup LSD for street cars - they can be noisy
09-16-2011, 12:29 PM
#21
Rennlist Member
Matt at GT gear deal with customers all over the world. Unless you are located in a war zone Matt will be able to get the parts or LSD shipped to you. If you want to find a used Cup LSD in your local then that's a different story. Will not recommend Cup LSD for street cars - they can be noisy
09-16-2011, 12:38 PM
#22
Admin
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Mike, what's the story behind your new affection for Megan? Did I miss a memo?
PS. CUP internals in the oem LSD are not noisy, but then again I am 3/4 deaf so..
PS. CUP internals in the oem LSD are not noisy, but then again I am 3/4 deaf so..
09-16-2011, 12:45 PM
#23
Nordschleife Master
Hello,
I figured I would just add a link to the definitive thread discussing the darn near useless OEM street LSD:
https://rennlist.com/forums/997-gt2-...sd-buster.html
I also want to put something out there for anyone who would prefer to use Cup Car components in their LSD instead of using ours. As John has mentioned, the 4 plate 996 GT3 Cup Car rebuild kits seem to be running out and it doesn't look like Porsche is going to replace them. PMNA here in the States has just been superceding the kit to the newer 8 plate kits and expecting consumers to buy them instead. Since they are catering strictly to racecars, this is a logical approach.
However, for someone with a dual purpose track and street vehicle, that clutch kit is just too aggressive. So, I am going to tell you how to make it work for you. The Cup Car internal stack is part of the problem. It leaves about .7mm of gap on an average street LSD if you just throw it in there. Not only is that too tight for a street car, but it's too many friction faces as well. But the solution is easier than you think.
What you want to do is leave out one friction disc and one plain steel plate per side when you rebuild it. The steel plate is 1mm thick and the friction disc is 1.15-1.20mm thick. So you are removing 2.15+/-mm per side. What you replace it with is a single steel disk out of your street diff. Those discs are roughly 2.0mm thick. You put it between the last 1mm steel plate and the Cup Car belleville washer on the outside of the stack. You've reduced the total stack height by about .3mm, taking it up to 1mm.
While this is not optimum, and most of you guys that we've done 4 plate LSDs or rebuilds for are running 1.4-1.6mm internal gaps, it makes the Cup Car kit liveable. You could go so far as to take out another pair of friction and steel plates, but then I start to worry about the wear since the friction face on Porsche's 1mm friction discs is nowhere as thick as our 2.1mm friction discs. Though the flip side would be that you'd have complete spare set of 4 friction discs to throw in there when you do wear out the first set without any further expense of parts the next time you've got to service.
Just some food for thought and a solution for people that time and/or distance prevents from using our parts. Or for someone who just plain feels that OEM is best. I'm not going to fault a guy for his opinion, even if it doesn't agree with my opinion on the subject.
Regards,
Matt
I figured I would just add a link to the definitive thread discussing the darn near useless OEM street LSD:
https://rennlist.com/forums/997-gt2-...sd-buster.html
I also want to put something out there for anyone who would prefer to use Cup Car components in their LSD instead of using ours. As John has mentioned, the 4 plate 996 GT3 Cup Car rebuild kits seem to be running out and it doesn't look like Porsche is going to replace them. PMNA here in the States has just been superceding the kit to the newer 8 plate kits and expecting consumers to buy them instead. Since they are catering strictly to racecars, this is a logical approach.
However, for someone with a dual purpose track and street vehicle, that clutch kit is just too aggressive. So, I am going to tell you how to make it work for you. The Cup Car internal stack is part of the problem. It leaves about .7mm of gap on an average street LSD if you just throw it in there. Not only is that too tight for a street car, but it's too many friction faces as well. But the solution is easier than you think.
What you want to do is leave out one friction disc and one plain steel plate per side when you rebuild it. The steel plate is 1mm thick and the friction disc is 1.15-1.20mm thick. So you are removing 2.15+/-mm per side. What you replace it with is a single steel disk out of your street diff. Those discs are roughly 2.0mm thick. You put it between the last 1mm steel plate and the Cup Car belleville washer on the outside of the stack. You've reduced the total stack height by about .3mm, taking it up to 1mm.
While this is not optimum, and most of you guys that we've done 4 plate LSDs or rebuilds for are running 1.4-1.6mm internal gaps, it makes the Cup Car kit liveable. You could go so far as to take out another pair of friction and steel plates, but then I start to worry about the wear since the friction face on Porsche's 1mm friction discs is nowhere as thick as our 2.1mm friction discs. Though the flip side would be that you'd have complete spare set of 4 friction discs to throw in there when you do wear out the first set without any further expense of parts the next time you've got to service.
Just some food for thought and a solution for people that time and/or distance prevents from using our parts. Or for someone who just plain feels that OEM is best. I'm not going to fault a guy for his opinion, even if it doesn't agree with my opinion on the subject.
Regards,
Matt
09-16-2011, 01:57 PM
#24
Rennlist Member
09-16-2011, 02:24 PM
#25
Matt at GT gear deal with customers all over the world. Unless you are located in a war zone Matt will be able to get the parts or LSD shipped to you. If you want to find a used Cup LSD in your local then that's a different story. Will not recommend Cup LSD for street cars - they can be noisy
Pack it well though.
09-16-2011, 02:51 PM
#26
Rennlist Member
For even faster turnaround, disassemble the LSD yourself, measure the spider gear assembly thickness (Matt can explain this), and just order the rebuild parts. It is not difficult to rebuild.
09-16-2011, 04:20 PM
#27
Addict
Rennlist Member
Rennlist Member
Hello,
I figured I would just add a link to the definitive thread discussing the darn near useless OEM street LSD:
https://rennlist.com/forums/997-gt2-...sd-buster.html
I also want to put something out there for anyone who would prefer to use Cup Car components in their LSD instead of using ours. As John has mentioned, the 4 plate 996 GT3 Cup Car rebuild kits seem to be running out and it doesn't look like Porsche is going to replace them. PMNA here in the States has just been superceding the kit to the newer 8 plate kits and expecting consumers to buy them instead. Since they are catering strictly to racecars, this is a logical approach.
However, for someone with a dual purpose track and street vehicle, that clutch kit is just too aggressive. So, I am going to tell you how to make it work for you. The Cup Car internal stack is part of the problem. It leaves about .7mm of gap on an average street LSD if you just throw it in there. Not only is that too tight for a street car, but it's too many friction faces as well. But the solution is easier than you think.
What you want to do is leave out one friction disc and one plain steel plate per side when you rebuild it. The steel plate is 1mm thick and the friction disc is 1.15-1.20mm thick. So you are removing 2.15+/-mm per side. What you replace it with is a single steel disk out of your street diff. Those discs are roughly 2.0mm thick. You put it between the last 1mm steel plate and the Cup Car belleville washer on the outside of the stack. You've reduced the total stack height by about .3mm, taking it up to 1mm.
While this is not optimum, and most of you guys that we've done 4 plate LSDs or rebuilds for are running 1.4-1.6mm internal gaps, it makes the Cup Car kit liveable. You could go so far as to take out another pair of friction and steel plates, but then I start to worry about the wear since the friction face on Porsche's 1mm friction discs is nowhere as thick as our 2.1mm friction discs. Though the flip side would be that you'd have complete spare set of 4 friction discs to throw in there when you do wear out the first set without any further expense of parts the next time you've got to service.
Just some food for thought and a solution for people that time and/or distance prevents from using our parts. Or for someone who just plain feels that OEM is best. I'm not going to fault a guy for his opinion, even if it doesn't agree with my opinion on the subject.
Regards,
Matt
I figured I would just add a link to the definitive thread discussing the darn near useless OEM street LSD:
https://rennlist.com/forums/997-gt2-...sd-buster.html
I also want to put something out there for anyone who would prefer to use Cup Car components in their LSD instead of using ours. As John has mentioned, the 4 plate 996 GT3 Cup Car rebuild kits seem to be running out and it doesn't look like Porsche is going to replace them. PMNA here in the States has just been superceding the kit to the newer 8 plate kits and expecting consumers to buy them instead. Since they are catering strictly to racecars, this is a logical approach.
However, for someone with a dual purpose track and street vehicle, that clutch kit is just too aggressive. So, I am going to tell you how to make it work for you. The Cup Car internal stack is part of the problem. It leaves about .7mm of gap on an average street LSD if you just throw it in there. Not only is that too tight for a street car, but it's too many friction faces as well. But the solution is easier than you think.
What you want to do is leave out one friction disc and one plain steel plate per side when you rebuild it. The steel plate is 1mm thick and the friction disc is 1.15-1.20mm thick. So you are removing 2.15+/-mm per side. What you replace it with is a single steel disk out of your street diff. Those discs are roughly 2.0mm thick. You put it between the last 1mm steel plate and the Cup Car belleville washer on the outside of the stack. You've reduced the total stack height by about .3mm, taking it up to 1mm.
While this is not optimum, and most of you guys that we've done 4 plate LSDs or rebuilds for are running 1.4-1.6mm internal gaps, it makes the Cup Car kit liveable. You could go so far as to take out another pair of friction and steel plates, but then I start to worry about the wear since the friction face on Porsche's 1mm friction discs is nowhere as thick as our 2.1mm friction discs. Though the flip side would be that you'd have complete spare set of 4 friction discs to throw in there when you do wear out the first set without any further expense of parts the next time you've got to service.
Just some food for thought and a solution for people that time and/or distance prevents from using our parts. Or for someone who just plain feels that OEM is best. I'm not going to fault a guy for his opinion, even if it doesn't agree with my opinion on the subject.
Regards,
Matt
09-17-2011, 04:38 AM
#30
Thanks
Thanks for all the feedbacks. Looks like Cup LSD is out for me as this car is mainly for street and only occasional track days. I'll consider the Guard rebuild. My workshop doesn't even know how to open up the LSD so let alone rebuilding it or change its internal. There are few mechanics knowlegeable about P cars in Singapore.