No LSD or Worn LSD?
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03-22-2007, 08:44 PM
#32
03-22-2007, 09:08 PM
#33
Burning Brakes
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Originally Posted by BrendanC
This is what an open diff looks like:
http://billsworkshop.com/P928S4/xpic...harger%202.mp4
http://billsworkshop.com/P928S4/xpic...harger%202.mp4
I'm in unchartered territory now. Can you tell anything from these pics?
03-22-2007, 09:15 PM
#34
Thats an open diff. NO Question.
03-22-2007, 09:16 PM
#35
But the good news is its very very clean.
03-22-2007, 09:32 PM
#36
Burning Brakes
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Good to know. Thank you. I guess everyone knows what an open diff will do now 
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So it should be filled with 100% "no slip" oil, without any slip modifiers, correct?
.So it should be filled with 100% "no slip" oil, without any slip modifiers, correct?
03-22-2007, 09:52 PM
#37
Originally Posted by JKelly
Good to know. Thank you. I guess everyone knows what an open diff will do now .
So it should be filled with 100% "no slip" oil, without any slip modifiers, correct?
.So it should be filled with 100% "no slip" oil, without any slip modifiers, correct?
03-22-2007, 11:43 PM
#38
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Originally Posted by JKelly
Good to know. Thank you. I guess everyone knows what an open diff will do now .
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or this...
03-22-2007, 11:57 PM
#39
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Originally Posted by JKelly
Good to know. Thank you. I guess everyone knows what an open diff will do now .
So it should be filled with 100% "no slip" oil, without any slip modifiers, correct?
.So it should be filled with 100% "no slip" oil, without any slip modifiers, correct?
03-23-2007, 12:12 AM
#40
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Yep I need wider tires 
I know I have an LSD, cause I had it installed.
I know I have an LSD, cause I had it installed.
Originally Posted by Alan
Andre - I think you must be trying too hard.... 
or need wider tires
Once both wheels loose traction the LSD/PSD or lack there of isn't going to make much difference until you get at least one wheel hooked back up... only then will you really be able to tell a big difference.
I think its intuitively easier to tell whats going on by provoking just 1 wheel to slip - pretty clear what is happening then... incl. whats slipping.
e.g. 1 wheel on dry pavement & 1 on slick wet or pavement & dirt (accepting the dust cloud).
Full dual rear burnouts... well I don't know about you but I'm not all that practiced at telling exatly whats going on.... except that I don't get to launch very fast that way & I can feel & hear the tire dollars dissapearing!
Alan
or need wider tires Once both wheels loose traction the LSD/PSD or lack there of isn't going to make much difference until you get at least one wheel hooked back up... only then will you really be able to tell a big difference.
I think its intuitively easier to tell whats going on by provoking just 1 wheel to slip - pretty clear what is happening then... incl. whats slipping.
e.g. 1 wheel on dry pavement & 1 on slick wet or pavement & dirt (accepting the dust cloud).
Full dual rear burnouts... well I don't know about you but I'm not all that practiced at telling exatly whats going on.... except that I don't get to launch very fast that way & I can feel & hear the tire dollars dissapearing!
Alan
03-23-2007, 12:15 AM
#41
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Originally Posted by Jim bailey - 928 International
very, very few 928s have had a slip added...and no one knows that better than I do 
About the only ones to add a slip are track junkies and the total number of tracked 928s is no doubt a two digit number.
About the only ones to add a slip are track junkies and the total number of tracked 928s is no doubt a two digit number.
03-23-2007, 03:12 AM
#43
Burning Brakes
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Originally Posted by SharkSkin
Actually, it depends on the circumstances... Sometimes an open diff will do this...
or this...
or this...
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03-23-2007, 09:10 AM
#44
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John,
as others have said, you absolutely have an open diff. IF there is absolutely no way for you to spin just one tire, you might have a defective open diff. Perhaps a cracked spider or shaft which cuases the diff to bind under load? That may also explain your noise???
But- looking at those stripes, it seems to me that the second "turn" should show some side travel if both rear wheels were spinning and lost grip. There doesn't seem to be any significant fish tailing which would indicate that at least one tire maintained some lateral grip, which is harder to do with LSD. Also, the inside (unloaded) tire left darker rubber indicating that it was spinning significantly faster. I would expect that with LSD, the outside (loaded) tire would leave a darker stripe...
I feel like Morisa Tomei in "my cousin Vinny". "would the 2 yutes please rise".
As far as the no slip - did you see my last post on the first page? Are we talking something different?
EDIT- I just realized that the second photo was photo-shopped... of course theres no lateral movement, it ws created but a non LSD car- duh!
as others have said, you absolutely have an open diff. IF there is absolutely no way for you to spin just one tire, you might have a defective open diff. Perhaps a cracked spider or shaft which cuases the diff to bind under load? That may also explain your noise???
But- looking at those stripes, it seems to me that the second "turn" should show some side travel if both rear wheels were spinning and lost grip. There doesn't seem to be any significant fish tailing which would indicate that at least one tire maintained some lateral grip, which is harder to do with LSD. Also, the inside (unloaded) tire left darker rubber indicating that it was spinning significantly faster. I would expect that with LSD, the outside (loaded) tire would leave a darker stripe...
I feel like Morisa Tomei in "my cousin Vinny". "would the 2 yutes please rise".
As far as the no slip - did you see my last post on the first page? Are we talking something different?
EDIT- I just realized that the second photo was photo-shopped... of course theres no lateral movement, it ws created but a non LSD car- duh!
Last edited by John V; 03-23-2007 at 10:39 AM.
03-23-2007, 04:12 PM
#45
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I'm with John on the spider issue -- After seeing the pic of the inside of your diff, it is absolutely NOT LSD. Another possibility is that your tires are such crap that they can never get traction, and/or are way overinflated.
With the car in gear, rear end lifted, you should be able to rotate one wheel and have the opposite wheel turn with little or no resistance. Any binding indicates a problem.
The noise could be the rear pinch bolt is loose and/or the input shaft bearing is worn.
With the car in gear, rear end lifted, you should be able to rotate one wheel and have the opposite wheel turn with little or no resistance. Any binding indicates a problem.
The noise could be the rear pinch bolt is loose and/or the input shaft bearing is worn.