Want a 991.2 with a 500hp NA engine?
07-03-2017, 07:35 AM
#31
Not interested in any Porsche GT product until the .2 GT3 engine passes muster, which for me means at least two years without significant drama.
07-03-2017, 11:48 AM
#33
Addict
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991.1 data from actual testing by Sport Auto, the German Sports car magazine (not merely factory claims).
As another data point, the street-legal Viper ACR generates over 1,700 pounds of downforce:
http://www.roadandtrack.com/car-cult...owing-economy/
07-03-2017, 12:09 PM
#34
RL Community Team
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This is wrong. All GT cars generate significant downforce (not merely a reduction of lift). 991.1 GT3 generated 157 pounds of REAR downforce at top speed and the 991.2 GT3 is claimed to generate 20% more which would mean about 188 pounds Rear downforce. Total downforce numbers including front axle were 255 pounds for 991.1 GT3 and would be 306 pounds for 991.2 GT3.
991.1 data from actual testing by Sport Auto, the German Sports car magazine (not merely factory claims).
991.1 data from actual testing by Sport Auto, the German Sports car magazine (not merely factory claims).
07-03-2017, 05:59 PM
#35
Three Wheelin'
Originally the wing on the GT3 road car was there for homologation because the race car needed to race effectively. Overtime it has been determined than underbody diffusers providing negative lift or suction are even more effective than the wing alone, new RSR case in point. The old 911 platform with wing but w/o diffuser became inadequate and uncompetitive. The R and .2 GT3 have a new design diffuser that are effective without the wing to provide high speed stability for all but race level track use. So why the objection to a wingless GT3? Buyers are insecure about image and wings on street cars have a poor image. Only a required OEM wing can justify and hope to negate the silliness of a huge track wing on a street car.
07-03-2017, 06:18 PM
#36
Burning Brakes
Whether one likes the look of the wing or not, the purpose of the GT3 wing is not high speed stability, but rather downforce to improve high-speed cornering. You can achieve high-speed stability simply by keeping downforce/lift at a neutral level and also making sure that any lift is greater in the front than the rear. Or conversely, that any downforce is greater in the rear than the front. Either condition promotes high-speed understeer, which is essentially the definition of stability.
For high-speed cornering, you want as much downforce as possible, while still maintaining the above balance. That's why F1 cars have so much downforce that they could drive on a track upside down at 200 mph. And so much drag that they decelerate about as hard as a 911 in full ABS when the driver simply lifts at 200.
For high-speed cornering, you want as much downforce as possible, while still maintaining the above balance. That's why F1 cars have so much downforce that they could drive on a track upside down at 200 mph. And so much drag that they decelerate about as hard as a 911 in full ABS when the driver simply lifts at 200.
07-03-2017, 06:42 PM
#37
Addict
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Originally the wing on the GT3 road car was there for homologation because the race car needed to race effectively. Overtime it has been determined than underbody diffusers providing negative lift or suction are even more effective than the wing alone, new RSR case in point. The old 911 platform with wing but w/o diffuser became inadequate and uncompetitive. The R and .2 GT3 have a new design diffuser that are effective without the wing to provide high speed stability for all but race level track use. So why the objection to a wingless GT3? Buyers are insecure about image and wings on street cars have a poor image. Only a required OEM wing can justify and hope to negate the silliness of a huge track wing on a street car.