Cars-Pickup-Truck: >>Porsche GT3

Porsche 911 GT3

Porsche 911 GT3

Manufacturer	Porsche
Production	1999-Present
Assembly	Stuttgart-Zuffenhausen, Germany
Class	Sports car
Body style	2-door coupe
Layout	RR layout
Transmission	6-speed manual
Wheelbase	92.7 in (2,355 mm)

996

Production	1999-2005
Engine	3.6L 380 hp H6
Length	174.6 in (4,435 mm)
Width	69.7 in (1,770 mm)
Height	50.2 in (1,275 mm)

997

Production	2006-Present
Engine	3.6L 415 hp H6, 3.8L 435 hp H6
Length	174.3 in (4,427 mm)
Width	71.2 in (1,808 mm)
Height	50.4 in (1,280 mm)

The Porsche 911 GT3 is as a high performance version of the Porsche 911 sports car. It is the latest in a long line of high performance models which began with the 1973 911 RS. The GT3, named after the FIA GT class it was intended for, has a 3.8 litre naturally-aspirated six cylinder engine which is based on the unit used in the Porsche 962 and Porsche 911 GT1 race cars.

Since it's launch in 1999 a number of variations, designed for both road and track, have been added to the range. The current range (997) includes two road and three racing models. In addition to this, Porsche are currently developing a hybrid version which uses two electric motors and a Kinetic Energy Recovery Systems which was initially developed for Formula One.

The GT3 has had a successful racing career both in the one make national Porsche Carrera Cup series, the international Porsche Supercup and also winning numerous championship and endurance races including the GT class of the American Le Mans Series seven times, the 24 Hours of Daytona outright and the 24 Hours Nürburgring five times.

996 Model range

The road going version of the 996 GT3, which was launched at the 1999 Geneva Motor Show, was a development of the Supercup racer which made it's debut at the season-opening Supercup round at the 1998 San Marino Grand Prix.^[1] Unlike the road car, which had a new water cooled engine, the GT3 used a development of the originally air-cooled 911 engine. Based on the unit used in the 962 and 911 GT1 race cars the GT3 featured a dry-sump with an external oil tank and split crankcase. Instead of using a fan and finnedcylinders to cool the engine, separate water jackets were added onto each banks of three cylinders with water pumped though a radiator. Unlike the 962 engine, which used six individual cylinder heads, the GT3 uses two cylinder heads, each covering a bank of three cylinders. The original version of the GT3 produced 360 PS (265 kW; 355 hp), compared to the 300 PS (221 kW; 296 hp) of the regular 996. The GT3 has enlarged brakes, a lowered, re-tuned suspension system, lighter-weight wheels and a new front bumper with matched rear spoiler to help increase downforce, thereby increasing grip.

Up to early model year 2004 production, the basic casting used for the crankcase of the GT3 was exactly the same as the air-cooled engine and still had the "964" casting number on the bottom of the crankcase. The casting was changed in mid-2004 to a "996" casting number crankcase to eliminate these external air-cooled remnants, but internally it remained the same. The six speed manual gearbox was based on the unit from the 993 GT2 with revised gear ratios.

As with Porsche's 911 RS models, the GT3 was devoid of any unnecessary items that would add weight to the car. Sound deadening was almost completely removed, as were the rear seats, stereo system, sunroof, and air conditioning, although automatic air conditioning and CD/radio became no-cost optional add-ons. In addition, Porsche offered a no-cost option called the Clubsport package. This option replaced the standard electrically adjustable leather front seats with manually adjustable racing seats finished in fire-retardant fabric, bolt-in half-roll cage, 6-point drivers racing harness, fire extinguisher (mounted in the front passenger footwell) and preparation for a battery master switch. The Clubsport option was never offered to US customers ostensibly due to the additional DOT crash testing that would have been required to allow US sales.

Porsche made significant updates to the GT3 for 2003, the first year the car was offered to US customers. Horsepower was raised to 381 hp (284 kW) and torque to 284 lb·ft (385 N·m), 80% of which was available from 2,000 rpm. The braking setup was upgraded, featuring 6-piston calipers on the front (rears remained 4-piston), and the Porsche Ceramic Composite Brake system was offered as an option. The new car also was updated to the 2002 911 facelift.

In track testing by American automotive journals, the GT3 managed a 0-60 mph time of 4.5 seconds and a quarter mile time of 12.0 seconds at 118 miles per hour (190 km/h). During skidpad testing the vehicle posted 1.03g. Porsche introduced a revised 911 GT3 RS to the European market in 2003, marking the last revision of the 996 platform car before its discontinuation in 2005. Porsche's official test-driver Walter Röhrlcompleted the Nürburgring Nordschleife with the 996 GT3 in 7 minutes 56 seconds, a feat which was used by Porsche to promote the car. Later, with the 996 GT3 RS, he managed 7 minutes 43 seconds.

A total of 1,890 996 GT cars were built.

996 GT3 RS

The Porsche 911 GT3 RS is a homologation model build in accordance with the FIA GT rules. The GT3 RS is lighter thanks to a polycarbonaterear window, carbon fiber hood and rear wing. Porsche also offered as an option ceramic composite brakes (PCCB) which as well as being lighter offers better heat and fade resistant than the cast iron units fitted as standard.

The RS has a slightly different engine specification to the GT3. The cylinder heads of the GT3 RS have reshaped intake and exhaust ports for race homologation. Porsche claim the same 381 hp (284 kW) power output as the standard GT3.

The RS has progressive rather than linear springs. The dampers are uprated and are between 10 and 15 percent stiffer than the normal GT3 in bounce and rebound. The wheel carriers are totally redesigned to maximise the improved dynamic camber control. The suspension top mounts can be turned 120 degrees to a cup car position. Both front and rear control arms are adjustable. The RS is 3 mm (0.1 in) lower than the standard car.

The RS rear wing delivers 35 kg (77 lb) of downforce at 125 mph (201 km/h). The RS has ram air ducts on the engine bay which force air into the intake with 18Mb of pressure at 187 mph (301 km/h) and this is enough to create an additional15 bhp (11 kW; 15 PS). That extra bhp cannot be homologated since the official engine output figures are certified on a dyno.

The original 996 GT3 RS had a production run from 2003 to 2005. The car was only available in white with either blue or red light weight wheels and "GT3 RS" inscription on the side. Only 140 right hand drive GT3 RS cars were built and 113 of those were officially imported into to the UK. The GT3 RS was not sold in USA or Canada.

997 Model range

In February 2006, Porsche revealed the latest street-legal version of the GT3, now built on the new 997 platform. Prior to that, 997 had already been in active race use for several months. In addition to a new 415 hp (309 kW) 3.6 litre flat-six engine, the vehicle features "zero lift" aerodynamics, meaning the car creates only aerodynamic downforce but no "lift", which pulls upwards and away from the road surface and affects overall grip. The vehicle now makes use of a modified, track oriented version of Porsche's active PASM suspension making this the first of Porsche's RS or GT3 versions to feature an electronically adjustable suspension system. Also available are a navigation system and Porsche's "sports chrono" gauge package, making this the most "friendly" lightweight track car the company has ever produced. The car went to sale in summer of 2006 and had a starting price of 106,000 USD. The RS was released in Europe in October 2006 and in North America in spring 2007.

The vehicle has a rated 0-60 mph time of 4.1 seconds and has a top speed of 193 miles per hour (311 km/h). Road and Track was able to achieve a 0-60 mph run in 3.8 seconds. Porsche's official test-driver Walter Röhrl completed the Nürburgring Nordschleife in 7 minutes 42 seconds with the 997 GT3. Cited in an interview with Mr. Röhrl by Swedish sports car magazine Automobil 5.06.

In 2009 Porsche launched the 2nd Generation 997 GT3, boasting an enlarged 3.8 litre engine producing 435 bhp (324 kW; 441 PS). It also featured a number of new options including dynamic engine mounts and a hydraulically lifting front axle to compensate for the low ground clearance. The rear spoiler was also modified along other parts of the bodywork. Deliveries in Europe commenced in October the same year.

997 GT3 RS

As with earlier models, such as the Carrera RS 2.7 of 1973 and the Type 964 911 RS of 1991, Porsche offered an RS version of the 997 GT3. In common with its predecessors, it provides a homologation model for use in a range of racing series.

Thanks to a close-ratio six-speed transmission with a single-mass flywheel, the engine revs up even more freely, thus enabling the 911 GT3 to sprint from zero to 100 km/h (62 mph) in 4.0 seconds while reaching 200 km/h (124 mph) in 13.3 seconds. Maximum speed is 310 km/h (193 mph).

The RS is 20 kg (44 lb) lighter than the GT3, weighing in at 1,375 kg (3,031 lb). This weight-saving was achieved by the use of an adjustable carbon fiber wing, a plastic engine cover, and a lightweight plastic rear window. The weight savings gives the RS model corresponding engine power to curb weight ratio of 300 bhp (220 kW) per tonne.

One characteristic of the new RS is the body, which is 44 mm (1.7 in) wider at the rear (a legacy from the Carrera 4 models with which it shares its shell) by comparison with the 911 GT3. The muscular-looking rear end conceals a wider track that not only improves directional stability but also increases the potential cornering grip of the two-seater coupe. On the other hand, drag is increased, and top speed reduced.

In addition to the new technology featured in this flat six motor car, the paint scheme and body panels are all designed specially for this car. For the RS version, the limited edition orange color was mixed specially for this car.

The American version of the RS has a standard rear window (not plexiglas) and the smaller 911 fuel tank to comply with rules of SCCA, Grand-Am, and IMSA. For Grand-Am races, the central locking wheel nut is replaced with the standard five-lug pattern required under Grand-Am rules.

Production of the first generation 997 GT3 RS ended in 2009. An estimated 1500 vehicles were delivered worldwide, with an estimated 413 of those directed to the United States.

For 2010, the new (or second generation) 911 GT3 RS received an additional 35 PS (26 kW; 35 hp) due to a new 3.8-liter flat-six, bringing total power output up to 450 PS (331 kW; 444 hp). This car will not be raced in the United States as both IMSA American LeMans has not approved the new car for competition. Grand-Am originally did not approve the car, but after performance issues (a Porsche team did not compete at the Indy Grand Prix of Alabama round), Grand-Am approved the second-generation car in April 2010.

Porsche test driver Walter Röhrl had intended to enter the 2010 24 Hours of Nürburgring on a standard road legal 911 GT3 RS, but had to withdraw due to health reasons from the team that comprised racers Roland Asch and Patrick Simon, plus journalists Horst von Saurma andChris Harris. The car, entered in cooperation with sport auto (Germany), is registered as S-GO 2400, and was driven from Weissach to Nürburg. The RS was modified according to safety requirements, which included a larger roll cage and fire extinguisher. As no race tyres were available for 19" rims, the 18" wheels of the Cup racers were used. Asch has qualified with 9:15, 42nd overall, and 9th among the 17 SP7 class entrants, only beaten by its race-prepped Porsche 997 siblings. In an otherwise disappointing race for Porsche, with the best race 997 finishing only 6th, the road legal car did 145 laps, only 9 less than the winning BMW, for place 13. It supposedly has to cover another 306km, on the Autobahn back home.

At 450 hp (336 kW), the 3.8 litre flat-six engine in the 997 GT3 RS is the most powerful six cylinder naturally aspirated engine in any production car with a 118 hp per liter output.

Road cars

Racing

Due to the absence of the official Porsche team in the 1999 24 Hours of Le Mans, only privateers with the nearly obsolete air-cooled 993 GT2 Turbo were expected to represent the marque, with few chances to beat the Chrysler Viper for GTS class honors. Yet, two new race versions of the water-cooled 996 GT3-R showed up, officially entered in the GT class by private teams, but the drivers involved and Porsche engineers in the pits indicated that it was an effort backed by the company. Even though these were the least powerful cars in the event, being the only entrants in the GT class, the new GT3-R was noticed by fans for its loud exhaust sound when driving in 1st gear through the pitlane, comparable to ex-Formula Oneengines of Judd. The better of the two cars, entered by the German Manthey Racing team, finished 13th overall, beaten by only two of the Vipers with an engine more than twice the displacement.

The 996 GT3-R were made available to privateer teams. In the 24 Hours Nürburgring of the year 2000, a factory-backed effort of the local Phoenix team managed to beat the Zakspeed Chrysler Viper that dominated this race from 1999 to 2002. The improved 996 GT3-RS version of 2001 was entered in countless races in the years to follow, scoring not only many class wins, but also overall wins at Daytona and Spa in 2003. In 2004, the 996 GT3-RSR was made available, with numerous improvements to the RS, including a sequential gearbox, which allows for faster gearshifts.

In 2005, the new 997-generation racing vehicles began to debut with the GT3 Cup, and was followed by the launch of the 911 GT3-RSR at the 2006 Spa 24 Hours. In VLN endurance races at the Nürburgring in 2007, the new car had teething problems, and the wide rear fenders reduced top speed. Yet, the Manthey entry won the last 4h race before the 24h event, and managed to win the big event also.

The following race versions were or are offered:

1999 996 GT3-R
2000 996 GT3 Cup
2001 996 GT3-RS
2004 996 GT3-RSR - with sequential gear box
2005 997 GT3 Cup
2007 997 GT-3 RSR
2008 997 GT3 Cup S
2010 997 GT3 Cup
2010 997 GT3 R

The new Porsche 997 GT3 R Hybrid made its debut at the 2010 Geneva Motor Show. The hybrid technology featured in the car was developed by the Williams Formula One Team and is based on their F1 Kinetic Energy Recovery Systems (KERS) which they did not race in 2009. Unlike other KERS that were developed for F1, the Williams system is based on using kinetic energy stored in a flywheelrather than batteries. The GT3-R has two electric motors, each developing 80 brake horsepower (60 kW), driving the front wheels to supplements the480 brake horsepower (360 kW) four-litre flat-six engine at the rear. It is planned to enter the car in the 2010 24 Hours Nürburgring. As part of the build up to the 24 hour race the GT3 Hybrid made it's racing debut at the 57th ADAC Westfalenfahrt at Nürburgring on March 27 2010.

Racing Achievements

Apart from numerous class wins, the GT3 won major events overall:

24 Hours Nürburgring in 2000, 2006, 2007, 2008, 2009
24 Hours Spa in 2003
24 Hours of Daytona in 2003

Also, at the Nürburgring, the GT3-RS and modified versions (with 3.9 litre engine) win many VLN races. ALMS 2009, 2008, 2005, 2004, 2003, 2002, 2000

The various national Porsche Carrera Cup series, and the international Porsche Supercup which is mainly run at Formula One events, also use the GT3 Cup.

Technical Specification

Model	Year	Capacity (L)	Horsepower	Torque	Weight	0-60 mph 0–96 km/h*	Top speed	Notes
996 GT3	1996	3.6	345 PS (254 kW; 340 hp) @ 6500 rpm	xxx	xxx	4.7 s	180 mph (290 km/h)
996 GT3	1996	3.6	345 PS (254 kW; 340 hp) @ 6500 rpm	xxx	xxx	4.7 s	180 mph (290 km/h)