Ever since its 2006 introduction, the Porsche Cayman has maintained a respectful distance from the 911, its performance a calculated exercise in sandbagging. Its mid-engine chassis always felt like it could easily handle another 100 horsepower or more—and it surely would have, except for model hierarchies and the need to stay in its lane. But over the years, Porsche gradually bestowed increasingly serious capability upon the Cayman (and Boxster) without hurting 911 sales in the slightest. The company eventually decided that the 911 is immune from fratricide, thus opening the door for the new 718 Cayman GT4 RS, a machine that sets out to answer the question, What if the 911 GT3 were mid-engined? It'll be a few more weeks before we can get behind the wheel ourselves, but Porsche invited us on a very fast ridealong to find out what happens when a Cayman gets a 493-hp engine transplant.
Caymans are usually more about handling poise than skull-crushing acceleration, but the 718 GT4 RS is a real beast, significantly faster than the well-established 718 GT4. The GT4 RS is powered by a naturally aspirated 4.0-liter flat-six taken straight from the 911 GT3 but turned around 180 degrees. It makes 493 horsepower at 8400 rpm, up from the regular GT4's 414 horsepower. Maximum torque is 331 lb-ft, delivered at 6250 rpm, and the engine screams all the way to its 9000-rpm redline.
Unlike the GT4, the GT4 RS model doesn't come with a manual transmission—a seven-speed dual-clutch automatic is the sole option. There are technical reasons for that, since Porsche claims it doesn't have a manual gearbox compatible with the Cayman that can handle this much torque, but this is also a philosophical matter. For RS models, speed takes precedence over all else, and PDK gives you quicker lap times.
It's too bad the RS doesn't offer clutch pedal, but the PDK does let you select gears with paddle shifters or the console shifter, which looks like a manual shift lever. And its shift logic follows your natural movement during hard driving—pull to upshift, push to downshift.
Porsche says that on the Nürburgring's Nordschleife, the GT4 RS beats the GT4 by 23.6 seconds, an incredible gap. The quicker time is a result of the extra horsepower working in concert with track-optimized chassis settings, aerodynamic tweaks, and stickier tires. The RS rides 1.2 inches lower than a standard Cayman, the underbody and rear diffuser are modified, and there is a new front spoiler lip with side blades. With the spoilers adjusted to their track settings, downforce improves by 25 percent over the GT4.
The result of all of these changes is extraordinary, even when experienced from the passenger's seat. The free-breathing 4.0-liter inhales through individual throttle bodies and reacts with a hard-edged immediacy that's rare in a world of turbocharged sports cars. The fierce soundtrack hits a lot of different notes over the engine's extensive rev range. It's loud too—the engine sits right behind the cabin, and you can literally feel it. Where other Caymans have small rear side windows, the GT4 RS has air intakes right up by your ears. With electrification seeming inevitable, future models of this ilk will have difficulty matching the visceral sensory overload delivered by the GT4 RS—or its claimed 3227-pound curb weight.
Upshifts and downshifts are punctuated by the appropriate exhaust crackle, and Porsche's claimed performance numbers should satisfy every enthusiast. Porsche says the sprint to 60 mph takes just 3.2 seconds and the quarter-mile arrives in 11.3—we think it'll go quicker. The top speed is a claimed 196 mph. All of those figures are markedly better than the regular GT4's.
The engine, while unbelievably responsive and powerful, doesn't seem to overburden the chassis—our driver was able to flick the car around on snowy surfaces with remarkable ease. The 718's steer-it-with-the-accelerator balance doesn't appear to be compromised by the RS's extra horsepower. The GT4 RS is also said to be lighter than a GT4 with PDK, and diets tend to have salutary effects on handling as well.
Extensive use of carbon-fiber-reinforced plastic no doubt helped get the weight down. The GT4 RS's hood, front fenders, seats, and rear wing all are constructed of the lightweight material. Some of that glorious carbon weave becomes visible when the $13,250 Weissach package is spec'd. That package also allows customers to replace the standard 20-inch forged aluminum wheels with forged magnesium wheels for an extra $15,640. As for visual cues, the Weissach package brings flared air-intake scoops in that rear-side-window spot, whereas non-Weissach cars have intakes flush with the body.
While the GT4 RS ought to be plenty happy on a racetrack, customers who want an actual turnkey race car can opt for the 718 GT4 RS Clubsport model, which starts at $229,000. Among other changes, the Clubsport trades its carbon-fiber bodywork for panels made of a natural flax-based fiber composite that's treated with new resins. Porsche says the Clubsport pieces are virtually as lightweight as carbon fiber but far more environmentally friendly.
The GT4 RS retails for an estimated $144,350, which seems almost a bargain given its performance and potential collectibility. But being able to afford one doesn't mean you'll get it any time soon: The production run isn't limited, but the waiting time is already around two years. If you were early, you could get one as soon as July, which is when U.S. deliveries start.
Whatever the wait, our initial ride indicates it'll be worth it. Short of the Carrera GT, this car might qualify as the most purist mid-engine Porsche of all time.