Previously, Porsche launched the 4.0L displacement 718 GT4, which has met the expectations of many self-absorbing fans for the 718, but there are still some enthusiastic fans who are not satisfied with this. After market research, Porsche implemented the gt4 RS research and development plan, the most important part of which was to replace the original MA223 on the GT4 with the MA275 engine on the 992 GT3. Although both engines are 4.0 displacement, they are definitely not as simple as direct plug & play.
But then again, Porsche has had this idea for a long time. Because when the 992 GT3 engine was developed, the dry sump of the MA275 engine and the complete set of fuel supply equipment had been reserved taking into account the mid-platform layout. The intake system of the GT4 RS is specially designed, the air intakes behind the left and right side windows are all air intakes, and the air will enter directly into a central pressure regulating chamber, and the complete air intake system is placed directly behind the driver, imagine how original and unreserved the sound that can be made by the independent throttle valve and the short intake duct.
You will definitely have questions, why the same engine on the 992 GT3 is 510ps, in the GT4 RS is 500ps, is Not Porsche specifically made a distinction. Porsche engineers give the answer here directly: this is because the GT4 RS exhaust pipe is too long. The main loss comes from the bending adjustment of the exhaust pipe to avoid driving the half shaft behind, which inevitably increases the exhaust back pressure. For this kind of high-rotation self-priming engine, a slight change in back pressure will have a significant impact. If this back pressure rise can be avoided in compliance with regulations, this engine can produce a maximum power of 510ps. In order to compensate for this rising back pressure as much as possible, Porsche has taken the larger exhaust valve on the GT2 RS and used it on the GT4 RS, trying to make the exhaust more smooth with a larger diameter. In general, there is no such thing as deliberately limiting or suppressing power, but because the GT3's exhaust pipe is shorter and faster to exhaust the exhaust gas, there is a significant improvement in high-speed power.
The PDK transmission, which works with the GT3 engine, was developed by Porsche specifically for the GT4 RS and is much better than the manual transmission on the GT4. No kidding! Because the gear ratio on that GT4 is so long, many bends often have to retreat to 2nd gear, which is very inconvenient.
So why not just take the PDK on the 992 GT3 and use it? The main problem is still limited by the space of the 718 body, so the PDK transmission on the GT4 RS is actually a combination of Cayman's PDK gearbox housing plus the gear set of the 991.2 GT3 RS. Due to the use of Cayman's gearbox housing, the electronically controlled LSD, the PTV Plus, is naturally absent due to space issues. Otherwise, it would be necessary to redevelop a gearbox housing, which is not economical. So Porsche took the mechanical 1.5way LSD on the manual version of the 992 GT3 and used it, and the dual-mass flywheel came from the GT4 Clubsport car.
Under this aggressive gear ratio setting, the GT4 RS is now only 115km/h in the 2nd gear, which is significantly lower than the PDK version OF GT4 125km/h, not to mention the manual version of 136km/h. And don't forget, the former has a red line of 1000 rpm higher than the latter.
In terms of chassis, unlike the GT3's front axle replacement with double wishbones, the GT4 RS suspension design structure remains consistent with the GT4, except that the spring stiffness is increased from 45N/mm to 100N/mm, and the rear axle is increased from 80N/mm to 140N/mm. In addition, the wheelbase of the front axle has increased by 6mm, and the wheelbase of the rear axle has increased by 8mm. The stiffness of the front and rear anti-roll bars is the same as that of the ordinary GT4, which is 42N/mm after the front 70N/mm, and the GT4 RS also has three anti-roll bar holes to adjust, corresponding to soft, moderate and hard three gears, and the hardest settings are used in the Neubei and Hockenheim tests.
The GT4 RS is also the first production Cayman model to be allowed to carry Cup2 R tires. The GT4 RS front spoiler can be adjusted in four segments of extended length, and the rear swan neck type is three-stage adjustable. However, when the factory is set before and after the low pressure state, at 200km/h is able to produce a total of 63kg downforce, and before and after the Performance gear setting, there is 100kg downforce, the same state of the ordinary version of GT4 downforce is 80kg.
Readers may also feel that lap speed is now less and less in the first place in the text. Yes, picking up the GT4 RS from Porsche's R&D center in Weissach to New North has made it clear along the way that lap speed is not the most important point to pursue for this car. Compared to track driving, the very direct throttle response, flexible front, more suitable for opening the window on the mountain road in the Alps to listen to the beautiful metal symphony of 9000 rpm. This multi-sensory common stimulus is perhaps what GT4 RS owners are more sought after. The next New York North Track is the second place for owners. While the GT4 RS wasn't built to break records, porsche's GT division really tapped into the handling potential of the 718.