Looking for a 95 993 with lsd
12-01-2007, 11:17 PM
#16
As I said best to contact Paul directly
Not always. Again if you look at the pic I posted , the same sort of thing is done w/ the ZF and GKN LSD used in our cars. When the outer or friction disks are alternated w/ the plain or inner disks the # of friction surfaces is maximised. Porsche used the % nomenclature though it has only peripheral bearing on the breakaway torque(actual effectiveness) of the diff.
on a 40% or 50% ZF the actual breakaway torque spec is between 30 and 57 lb-ft, On a 75% or 80% the actual breakaway torque spec is between 43 and 85 lb-ft. Other than the stacking sequence breakaway torque is adjusted by using different thickness plates to adjust the static preload.
Two clutch plates is a four friction surface config. From many years of working on Hewland diffs, most recent being their Powerflow, I had a habit of calling Porsche ramps by angles where as Porsche uses a % lock. Percentage lock is a function of torque applied, cF, lubricant etc. Which is why I never understood using a percentage figure vs. ramp accel and decel angles to label a ramp or side rings as Hewland likes to call them.
on a 40% or 50% ZF the actual breakaway torque spec is between 30 and 57 lb-ft, On a 75% or 80% the actual breakaway torque spec is between 43 and 85 lb-ft. Other than the stacking sequence breakaway torque is adjusted by using different thickness plates to adjust the static preload.
