Pixs of US GT3 RS
02-08-2007, 02:52 AM
#77
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Originally Posted by Carrera GT
You will very likely go to full soft in the fronts.
Then there is PASM. The non predictable self stiffening device. You might think the car is balanced, but at the limits, the linear front springs and the progressive rear springs should promote oversteer.
Fortunately the fix is simple:
02-08-2007, 03:07 PM
#78
Originally Posted by NJ-GT
CGT, I think there is something wrong with spring rates on this car. If you have to run the front bar full soft and the rear one full stiff to get the car balanced, that doesn't leave too much room for adjustment.
Then there is PASM. The non predictable self stiffening device. You might think the car is balanced, but at the limits, the linear front springs and the progressive rear springs should promote oversteer.
Fortunately the fix is simple:
Then there is PASM. The non predictable self stiffening device. You might think the car is balanced, but at the limits, the linear front springs and the progressive rear springs should promote oversteer.
Fortunately the fix is simple:
I like the feel of the 996 GT3 with the ride height and corner balance about right and the bars at 4/5 and 3/4 -- I'm wondering if they would just bolt up to the 997 to compare.
I spoke with a tech who sets up street GT3s with the rear bar softer. The idea being to let the car take some "set" with less roll stiffness and the weight transition to the rear (if driven reasonably competently) is the important move which keeps both rear wheels planted -- if roll is too stiff in the rear, the outside rear tire doesn't load up enough to stick (and this seems to be happening to me.)
Lots of things to learn about this car. I need a book to read on the new stuff. I just searched for "997 Cup cars for Dummies" but it's sold out at Amazon.
Nice pic. Is that an RSR with intermediate wets? CF rear bumper cover. But no all the threaded tie rods. Maybe a Cup car but they have conventional sways, not the blade type, I think. Anyway, curious.
02-08-2007, 03:33 PM
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I have run the GT3 at Willow Springs and I was impressed with the handling of the car. I had it corner balanced and aligned (track specs in the manual) prior to running it at the track. I started with 29/32 F/R hot but found it too soft and the front tire would roll. Going to 33/35 was an improvement but I found it would still roll over on the front tire. I was running the stock sway bar settings 2 off soft front and full stiff rear. I believe the front camber and toe needed to be more aggressive and I tightened the front bar to 1 off soft.
I am going to run her again monday to see if the changes improve the balance. Overall she handled very well and these changes are only minor tweeks to get the front tire to remain flat under extreme load.
I am going to run her again monday to see if the changes improve the balance. Overall she handled very well and these changes are only minor tweeks to get the front tire to remain flat under extreme load.
02-08-2007, 04:45 PM
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Originally Posted by Carrera GT
I think the imbalance is the driver at this point. I'll get around to criticising the car once I get some more seat time. : ) For now, any time the bars aren't about equal, you have to wonder. And having the car arrive full stiff in the rear is a bit odd -- and one less adjustment option than the 996.
I like the feel of the 996 GT3 with the ride height and corner balance about right and the bars at 4/5 and 3/4 -- I'm wondering if they would just bolt up to the 997 to compare.
I spoke with a tech who sets up street GT3s with the rear bar softer. The idea being to let the car take some "set" with less roll stiffness and the weight transition to the rear (if driven reasonably competently) is the important move which keeps both rear wheels planted -- if roll is too stiff in the rear, the outside rear tire doesn't load up enough to stick (and this seems to be happening to me.)
Lots of things to learn about this car. I need a book to read on the new stuff. I just searched for "997 Cup cars for Dummies" but it's sold out at Amazon.
Nice pic. Is that an RSR with intermediate wets? CF rear bumper cover. But no all the threaded tie rods. Maybe a Cup car but they have conventional sways, not the blade type, I think. Anyway, curious.
I like the feel of the 996 GT3 with the ride height and corner balance about right and the bars at 4/5 and 3/4 -- I'm wondering if they would just bolt up to the 997 to compare.
I spoke with a tech who sets up street GT3s with the rear bar softer. The idea being to let the car take some "set" with less roll stiffness and the weight transition to the rear (if driven reasonably competently) is the important move which keeps both rear wheels planted -- if roll is too stiff in the rear, the outside rear tire doesn't load up enough to stick (and this seems to be happening to me.)
Lots of things to learn about this car. I need a book to read on the new stuff. I just searched for "997 Cup cars for Dummies" but it's sold out at Amazon.
Nice pic. Is that an RSR with intermediate wets? CF rear bumper cover. But no all the threaded tie rods. Maybe a Cup car but they have conventional sways, not the blade type, I think. Anyway, curious.
02-09-2007, 02:26 PM
#81
Originally Posted by grussell
I have run the GT3 at Willow Springs and I was impressed with the handling of the car. I had it corner balanced and aligned (track specs in the manual) prior to running it at the track. I started with 29/32 F/R hot but found it too soft and the front tire would roll. Going to 33/35 was an improvement but I found it would still roll over on the front tire. I was running the stock sway bar settings 2 off soft front and full stiff rear. I believe the front camber and toe needed to be more aggressive and I tightened the front bar to 1 off soft.
I am going to run her again monday to see if the changes improve the balance. Overall she handled very well and these changes are only minor tweeks to get the front tire to remain flat under extreme load.
02-09-2007, 02:28 PM
#82
Originally Posted by DarrellC
I believe it's a pix of a 997 Cup Car. Blade type sway bars come stock on them.
02-16-2007, 01:18 PM
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Originally Posted by Carrera GT
It's much more likely to be a Cup and the tire is an intermediate, but it's still narrow for an RSR and I can't see the bolt-on fender flares, so I guess it is a Cup, but I'm told they don't have blade type anti-roll bars, but maybe there's some other rules or class that allows for the upgrade.
