History of the Porsche 911 GT3
Fri, 12/23/2011 - 16:35 — admin
During the 964 RS and 993 RS era, the comfort and hardcore versions both carried the RS badge. In fact many who ordered the comfort spec version had also replaced many of the “unnecessary” weight-bearing items like the power windows, radio and air-conditioning something which was instrumental in helping Porsche decide in the future of their RS models. Also the price range was similar within the RS family limiting Porsche's profits. However much had been learnt during this time to mass produce these special models on the production line instead and Porsche planned to do this during the 996 model especially with the new product, the GT3. You could say the genetic mother for the GT3 was the 964 RS Touring.
Ostensibly the Porsche 911 GT3 was made for the purposes of FIA homologation to race in the GT3 category as well as become their Porsche Supercup race car. Porsche's Motorsport arm was tasked to develop this new special “hot” model, essentially in essence the comfort version of the aforementioned RS models as the GT3 sold with all the creature comforts of the 911 Carrera range. But the plot was really thicker than that because Porsche actually wanted to return to GT1 racing and had engineer Hans Mezger design a new race engine for GT1 racing. The cost for this new engine was far too much to get Boardroom approval. They had to come up with a clever plan.
That plan involved using the Mezger flat six on all future production high-powered 911s to help defray the development and manufacturing cost over what they hoped would be thousands of engines. That list would include the Turbo, Turbo S, GT3, GT3 RS, GT2 and GT2 RS models (and not forgetting all the GT3 RSR, Cup, Supercup versions) in the 996 and 997 series. At least that was the plan but the last 997 Turbo and Turbo S got the new DFI engine from the normal production line spelling the end of the Mezger engine era with a deserving send off with the GT3 RS 4.0.Porsche 911 GT3 (Type 996 mk I)
So fortunately for the 996 GT3 mk I, it was the an early recipient of this marvellous engine. When it was first introduced it was a puzzle as to what this GT3 really stood for as it did not go through any lightening and chassis rewelding like the previous 964 RS and 993 RS cars. But Porsche had already planned for a much stiffer standard 996 chassis reaching 30,000 Nm per degree of torsional stiffness which is more than a match for a rewelded 993 chassis even in its standard form. For the GT3 models Porsche chose to use the C4 body as it was a bit stiffer thanks to the forward transmission tunnel design.
Porsche by now had decided that no longer were normal production specials to be made at their Weissach Motorsport facility, using up Motorsport technicians' and engineers' precious time. All the GT3s, and RS's were to be made and assembled at Zuffenhausen. Motorsport was to plan and design the engine and chassis components that could be assembled like any other model on the main production line.
The GT3’s technical ingredients originated from the Weissach motor racing department: separate oil tank for the dry sump lubrication system, GT1 crankcase, dual-mass flywheel, differential lock, titanium connecting rods plus modified engine and transmission mounts and an 89-litre fuel tank. The result was an output of 360 hp (265 kW) from a displacement of 3.6 litres, accelerating the 1,350 kg GT3 to 100 km/h (62 mph) in 4.8 seconds. With a top speed of 302 km/h (188 mph), the 911 GT3 was also optionally available with a Clubsport package for use in motor racing.
Of course we now know that Porsche had planned for an RS but for some reason not with the GT3 mk I. The GT3 would become the Comfort version of the RS but now it would not carry the illustrious RS moniker. That would be reserved for something rather more special and far more expensive(more profits), a rather clever piece of marketing. The GT3 then would not cost to much more than a normal Carrera S but would still qualify for homologation under GT3 regulations and still sell in significant numbers without costing Porsche too much to make. Between 1999 and 2000 numbers of the 996 GT3 hit 1868 with many buyers believing this was the RS incarnate.
They were not completely wrong as the GT3 made all the right moves and all the right noises. Thanks to what they have learnt over the years, the GT3 was the essence distilled from the original rough and ready 2.7 RS. But after so many years Porsche Motorsport had developed a few tricks of their own and was ready to put it to use in the GT3 mk II as the GT3 RS, marking the return of a most iconic name in the annals of Porsche history.Porsche 911 GT3 (Type 996 mk II)
When all the mk I GT3's were snapped up, many were left clamouring for more and still wondering what had really hit the market. Was it truly as many believed, the RS incarnate or merely another of the numerous derivatives that Porsche was about to unleash upon the world? Perhaps this favourable response to the first GT3 had surprised Porsche but it could well be they had planned it all along. However if they really had planned it so well, then there should have been a mk I GT3 RS instead of only waiting for the next facelift. We must admit it is rather intriguing but we may never know the real answer.
It would seem after another three long years Porsche finally had a plan and they put together the mk II GT3 with a 381 bhp engine up from the 360 bhp previously. Perhaps they felt this would make a better RS and in late 2003 the 4th generation 911 RS was launched after a hiatus of seven years. During this time it was still difficult to predict whether Porsche was really planning a succession of RS cars as they were few and far between, unlike the present where the persistence of the RS lineage has been well proven and truly prolific with more RS versions than GT3.
By now the protocol had became clearer. While the older RS cars had a comfort model, this would now beome the standard GT3, which oddly can be ordered with Club Sport spec. However the RS version of the GT3 would receive even more fettering in the body and chassis areas mainly to lighten and have a race spec suspension.
The mk II GT3 engine was revised to develop 21 bhp more but essentially was the same with a separate oil tank for the dry sump lubrication system, GT1 crankcase, dual-mass flywheel, differential lock, titanium connecting rods with modified engine and transmission mounts and an 89-litre fuel tank. The result was an output of 381 bhp from the same displacement of 3.6 litres, accelerating the 1,380 kg sports car to 100 km/h in 4.5 seconds and a top speed of 306 km/h.
The biggest differences came from the tyres switching from the original Michelin Pilot Sport 1 to Pilot Sport 2 and the steering ratio from the almost-too-quick rack in mk I to the kinder variable-ratio rack in mk II. This removed the darty handling but some still loved the sharpness of the mk I GT3.
Of course the GT3 RS finally made its appearance based on the mk II 996 GT3 but with even less weight and a more focused suspension. This became the blueprint for the future GT3/RS cars of the future 911 models. This mk II 996 GT3 was homologated for sale in the USA unlike the mk I. During 2003 and 2004 some 2313 GT3s were produced but surprisingly in the same period only 682 GT3 RS's were made.Porsche 911 GT3 (Type 997 mk I)
As of the autumn of 2006, the GT3 returned to the styling of the original with a sculptured flowing rear spoiler rather than the flat slab RS variety. This GT3 was tuned for trackday events but the rose jointed suspension possessed an uncanny ability to ride comfortably over poor tarmac. The 997 GT3 RS version was characterised by the performance and unadulterated experience of driving a racing car, but simultaneously met all of the requirements for road-legal sports cars. The engine was the same for both and retained its displacement of 3.6 litres but offered an impressive output of 415 hp (305 kW) at 7,600 rpm reaching 115.3 bhp per litre but with a wider 44mm chassis and 20 kg lower weight the RS had even better performance.
The six-speed manual transmission was also adapted to the new GT3 engine’s extended speed range by reducing the gear ratios. This resulted in acceleration from 0 to 100 km/h (0-62 mph) in a mere 4.3 seconds, with the GT3 reaching a speed of 160 km/h from a standing start in 8.7 seconds. The 997 GT3 mk I has a top speed of 310 km/h.
The new body of the 997 had 10% more rigidity now reaching a massive 33,000 Nm per degree. Also the development of certain polymers that could be used in thin layers to isolate the suspension without producing any deflection has to be the greatest triumphs of the mk I 997 GT3. Porsche has also added PSM as well as TC to make the 415 bhp less of a handful. At this point the GT3 had reached RS levels of handling and performance but did not have the RS certification on its ownership papers which is a big deal in these circles. The RS version of this GT3 goes over the top with lightening and suspension uprating producing a real street-legal race car. For many others the GT3 is more than sufficient especially when the rear spoiler looks so good compared to the RS version. Between 2005 and 2007 the factory produced 2378 GT3s but the GT3 RS got more popular and hit 1909 in sales.Porsche 911 GT3 (Type 997 mk II)
The 997 mid-life face lift was a bit more than just that, it encompassed numerous detail changes underneath, the most significant of which was PDK and the Direct Fuel Injection (DFI) to reduce emissions and bump up power. However the DFI technology was not available on the Mezger engine and the GT3 had to soldier on with sequential port injection. But that did not stop Porsche from upgrading the engine in the way it knows best.
The Porsche 911 GT3 now achieved an even higher standard in its two main qualities: power and driving dynamics. Maximum output of the naturally-aspirated six-cylinder reached 435 bhp (320 kW), up 20 bhp over the previous model in part thanks to a displacement hike to 3.8-litres. In particular, the flat-six power unit carefully upgraded for even more muscle and performance offered a significant increase in torque at medium engine speeds very noticeable above all in everyday use.
Road performance of the new GT3 has also been enhanced once again, with the car accelerating
The writing is already on the wall for the Mezger engine in 2009 as stringent EU regulations come into effect. In its 3.6-litre guise it had reached 415 bhp using port fuel injection. A massive 115.3 bhp per litre but to lift the power without even more revs would need a bigger bore and the engineers hogged it out to 102.7mm from 100mm, keeping the stroke the same at 76.4mm. This is perhaps the biggest bore the Mezger design could take before reliability suffered. Even the monster RS 4.0 keeps the bore at 102.7mm but adopts a stroke of 80.4mm and ups CR to an astounding 12.6:1.
Although the 3.8-litre GT3 gave rise to the GT3 RS 3.8, it was soon supplanted by the RS 4.0 simply because the 991 was on its way and as Andreas Preuninger, head of Porsche Motor Sport put it, they already had the 4.0 engine lying around for at least a couple of years before the RS 4.0's introduction, just was waiting for the right time. As we all know they had to release the 911 GT2 RS earlier in order to reclaim the Nordschleife crown from the Nissan GT-R. Besides the owners of the GT3 RS 3.8 barely had time to break-in their cars when Porsche announced the existence of the GT3 RS 4.0 which upset quite a few owners of the GT3 RS 3.8.
But for the Motor Sport department it is mission accomplished. The Mezger engines had played out the entire gamut of power and displacement range, sometimes even with the help of turbocharging. Over a period of 10 plus years it began life at 360 bhp and finished as a naturally aspirated 500 bhp and the incredible 620 bhp turbo-motor of the GT2 RS. This great engine had played the biggest part in legendary models like the 911 GT3, GT3 RS, GT2, GT2 RS, Turbo, Turbo S and the whole slew of proper racing engines from the GT1 to the GT3 RSR.
The other aspect of the GT3 is the body. It began as a narrow body Carrera 4 with a width of 1765mm. Even as the mk II GT3 it shared the narrow body with the GT3 RS. This changed as it progressed into the 997 because the 997 GT3 width grew to 1808mm, essentially a wide body in the 996 but the GT3 RS went out to 1852mm as the extra width results in greater cornering stability not to mention it is justification for the extra moolah you have to part with to acquire a RS over the GT3. Weight remained somewhat similar for the GT3s starting with 1350 kg, gaining 10 kg to 1360 kg as the 996 mk II. Once it became the 997 GT3 it really got heavier weighing in at 1395 kg and stayed that way even as the engine went up to 3.8-litres as the final iteration of the current series of GT3. Total number of 997.2 GT3 was 2256.