997 GT2 Differential
#32
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It was a bad tire!
The car had been CPO'ed and received a brend new set of Michelin Pilot Sport Cups, but one of the rears was defective. This was identified by switching the wheels & tires from side to side & test driving the car. The yaw was then exactly reversed! Right under acceleration, left under deceleration. The Wheel / tires were also tested on a "Road Force" balance machine, one rear produced 50lbs of load while the other was 20 lbs. The acceptable limit is 20 lbs. They are being sent to Michelin with the Road Force info for a claim to cover the cost of Replacent.
As the Diff was also worn and had basically zero pre-load I took the opportunity to install a Guard GT2 Club diff as well.
The car now runs straight as an arrow, and I can now enjoy driving it to the fullest!
The car had been CPO'ed and received a brend new set of Michelin Pilot Sport Cups, but one of the rears was defective. This was identified by switching the wheels & tires from side to side & test driving the car. The yaw was then exactly reversed! Right under acceleration, left under deceleration. The Wheel / tires were also tested on a "Road Force" balance machine, one rear produced 50lbs of load while the other was 20 lbs. The acceptable limit is 20 lbs. They are being sent to Michelin with the Road Force info for a claim to cover the cost of Replacent.
As the Diff was also worn and had basically zero pre-load I took the opportunity to install a Guard GT2 Club diff as well.
The car now runs straight as an arrow, and I can now enjoy driving it to the fullest!
#33
Instructor
Thread Starter
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My car had 7,500 miles on it when I acquired it. I understand the plates in the stock diffs wear quickly causing the pre-load to go to zero, although I still think they work when the ramps lock them up under acceleration & deceleration.
#34
Trucker
Rennlist Member
Rennlist Member
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Ok thanks Johnb55...I think that I understand. Next week I will get a chance to drive my GT2 and I cannot wait! Out of curiosity, does the Gaurd GT2 Club Diff make a lot more noise than what your stock diff? IE) At low speeds, turning, etc...? Or is it totally transparent.
#35
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You can spec Guard to make the diff any way you want. I believe mine is a GT2 PRO 60/40 with 55lb preload. That means- 60 degree ramp acceleration, 40 degree ramp decel.
That may or may not be what you want. Talk to Guard for a better understanding of your needs.
That may or may not be what you want. Talk to Guard for a better understanding of your needs.