You might first want to see all the modifications of the 911 991


Porsche 911 991 GT3 (2013-2015)

Date of unveil by Porsche AG: March 4, 2013
Premiere: March 5, 2013 Geneva Motor Show
World market launch: August 2013

 © Porsche

Technical specification and comparison

Modification No. of
seats
Gearbox Engine kW lb-ft Nm 60 mph 100 km/h 160 km/h 200 km/h mph km/h kg lb W/lb W/kg Nord-
schleife
2013 911 991 GT3 2 PDK 7-speed 3.8B6 350 324 440 3.3 sec. 3.5 sec. 7.5 sec. 11.4 sec. 196 315 1430 3153 111 245 7:30
2011 911 991 Carrera S WLS 4 PDK 7-speed 3.8B6 316 324 440 *3.8 sec. *4.0 sec.     190 306 1415 3120 101 223  
2011 911 997 GT3 RS 4.0 2 manual, 6-speed 4.0B6 368 338 460 3.8 sec. 3.9 sec.   11.9 sec. 193 310 1360 2998 123 271 7:27
2009 911 997 GT3 3.8 2 manual, 6-speed 3.8B6 320 316 430 3.9 sec. 4.1 sec.   12.3 sec. 194 312 1395 3075 104 229  
In the first column is year of introduction, add +1 for model year. * with Launch Control.


Before the production of the 991 GT3 started, 14.145 GT3 cars of 996 and 997 generations were made between 1999-2012.

The many questions

The 991 GT3 came with more questions than answers. Why is the "lightweight 911" so heavy? Why isn't the manual gearbox available? Will it be available for the RS? Why does it have 20" wheels, while it is proven that 18" is optimal for racing use.

Engine

The new 3.8-litre GT3 engine is a technological marvel. As there are rules and therefore restrictions for the racing cars, the street-legal 991 GT3 has more power than the 991 GT3 Cup. Both have 3.8-litre engines, but the racing variant has 338 kW compared to the street verson's 350 kW. The street engine has a rev limitter set 500 revolutions higher, at 9000 rpm instead of 8500 rpm in the 991 GT3 Cup. Although not as powerful, the racing version is 255 kg/562 lb lighter.

Engine problem on early cars

Porsche press release from March 19, 2014, said the engines of the first 785 produced 991 GT3 will be replaced by the Porsche Centres. They found the engine could be damaged by the loosened screw joint on the connecting rod, which damaged the crankcase and led to leakage of oil which ignited.

Gearbox

Even though the GT3 version of the PDK gearbox is 2 kg / 4 lb lighter than the unit in the 911 Carrera, the car is suffering 18 kg / 40 lb weight increase due to the PDK. The PDK comes with a "paddle-neutral" feature. If the driver pulls both shift paddles simultaneously, both clutches are opened and the flow of power from engine to real wheels is cut off. The driver might need this to neutralise the car when it is understeering. Once both shift paddles are released, the clutch engages again. Not as natural as it is with manual gearbox, but aiming in direction.

Tyres

The 991 GT3 is equipped with Dunlop Sport Maxx Race tyres, a new alternative to the Michelin Pilot Sport Cup tyres. The sizes are 245/35 ZR20 (91Y) N0 and 305/30 ZR20 (103Y) XL N0.

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Article © James Herne / Stuttcars.com


Sales catalogue

PDF 2013/03 911 GT3 (24 MB)


Continue to 991 GT3 RS

Anniversaries

Sep, 2828th birthday of the 911 964 (1988)
Oct, 01 – 20th birthday of the Boxster 986 (1996)
Oct, 29 – 76th birthday of Hans-Peter Porsche (1940)
Nov, 15 – 41st birthday of the 924 (1975)
Nov, 19 – 8th birthday of the Boxster 987.2 (2008)