The incredible new 2018 Porsche 911 GT2 RS is the fastest and most powerful 911 ever offered — find out how Porsche created such a capable supercar-beater right here.
Read the 2018 Porsche 911 GT2 RS First Drive right here.
Lightweighting
The GT2 RS body in white starts life as a 911 Turbo, made from aluminum and steel. Removing the rear seats saves 22 pounds, replacing the standard front seats with ones built around a carbon-fiber structure saves 31 pounds, and ditching the 911 Turbo’s all-wheel-drive system saves 110 pounds. The titanium exhaust weighs 15 pounds less. Front trunklid, front fenders, front wheel arch vents, exterior mirror covers, rear intake vents, and parts of the rear fascia are made from carbon fiber. The engine cover is also carbon fiber, with carbon-fiber hinges.
The roof is magnesium, which saves 2.2 pounds. The front and rear fascias are made of a lightweight polyurethane with tiny hollow glass spheres in it. The intercooler supports made from handlaid carbon fiber, and although the intercoolers are bigger, each assembly is 3.3 pounds lighter. Glass is lightweight Gorilla Glass, similar to that developed for mobile phones, lighter than the polycarbonate previously used on special 911s, and legal for road use in the U.S. Inside, lightweight carpets save 6.6 pounds. The cable harness 1.1 pounds lighter.
Weissach Package
This $31,000 option delivers some unique cosmetics—a body-color stripe over the car and Weissach package badging that includes a map of the legendary test track at Porsche’s R&D center—but the money also buys you an additional 60 pounds in weight savings.
The magnesium roof panel is replaced with one made of carbon. Normally this would be heavier, but an innovative three-layer design with a lightweight core means it’s 1.1 pounds lighter than the metal version. A titanium roll cage—not available in the U.S.—is nearly 20 pounds lighter than the same item made from steel. Preuninger says the Weissach package’s center lock alloy wheels might look a little old fashioned, but that the cross-spoke BBS motorsport design delivers the lightest and stiffest wheel. Made from forged magnesium, the wheels save a hefty 25.3 pounds of unsprung and rotating mass.
Perhaps the coolest part of the Weissach package is something you can’t see: New stabilizer bars and coupling rods that are made from carbon fiber, saving 12.1 pounds.
Turbochargers
“It’s not a chipped Turbo S,” says Porsche GT chief Andreas Preuninger of the GT2 RS engine. Although still 3.8 liters, it has a different crankcase with different main bearing seats, bespoke pistons that reduce the compression ratio, and different exhaust manifolds with 25 percent larger outlets.
But the key difference between the two engines is the size of the turbochargers. Although the Turbo S turbos have 2.2-inch turbines and 1.9-inch compressors, the GT2 RS’ turbos have 2.6 inch turbines and 2.1 inch compressors.
“If any tuner in the world tells you he can make 700 hp with the regular Turbo engine, don’t believe them,” Preuninger says. “It’s physically not possible. The Turbo S turbo can support maybe 640 hp, but then it runs out of revs and runs out of boost. It’s simply too small.”
Intake Air Management
“We are at a disadvantage compared with some competitors because our engine is right at the rear of the car,” Preuninger says. “We have to bring air back there in enough quantity to make 700 hp, and you need a lot of oxygen for that.”
To help, the scoops on the engine cover lead to a new airbox with five tubular filter elements that offer the maximum surface area for the size of package and deliver 15 to 20 percent more airflow. The intercoolers are 15 percent bigger and sit lower in the car, and a system that sprays water on the intercooler matrix when intake air temperatures exceed 122 degrees F, with 90 percent throttle openings, can reduce intake air temperature by as much as 68 degrees.
Preuninger says early in the GT2 RS’ development, the powertrain engineers figured the system would be worth looking at if it showed a reduction of 40 degrees, and they were stunned when testing showed reductions of up to 60 degrees. “It’s a real example of how you can’t calculate everything,” he says. “You have to try stuff out.”
The water spray system is fed by a 1.3-gallon tank, and because of its extreme operating parameters, Preuninger says it won’t often need refilling. If it does run dry, the engine management system simply dials back the available power. Refilling the tank, which is mounted in the trunk and easily accessible, is as easy as buying a bottle of distilled water.
Brakes
The brakes are the same as those on the GT3 RS, with one crucial difference. Although the GT3 RS featured big turning vanes on the front control arms to guide cooling air onto the front rotors, on the GT2 RS cooling air enters via NACA ducts on the trunklid and is directed downward onto the rotors.
“The GT3 RS system was very bad for additional drag and killed downforce,” Preuniger says. “This system is drag neutral and creates downforce while better cooling the brake rotor. There are still turning vanes, but they are a lot smaller so don’t impact drag. This is a win-win-win situation we are very happy about.”
Chassis Tune
The wheel carriers and control arms are shared with the GT3 RS. Ride height, camber, caster, toe, and stabilizer bar settings are all adjustable. The big change is in the spring rates. The front springs are 2.6 times stiffer than that of the GT3 RS, and the rear springs are 33 percent stiffer. “It’s more like a race car now,” Preuninger says. “It’s a lot less prone to roll, yaw, and pitch motions on the track, but to compensate when you’re driving it on the street, the stabilizer bars are softer.”
All chassis links are now racer car-style ball joints. “This makes the car incredibly precise,” Preuninger says. “It results in a little road more noise, and you hear the braking more, but most people who buy this car will put up with that.”
Downforce
Both the giant rear wing and the front splitter can be independently switched between road and track downforce settings. In road settings, the wing can generate up to 456 pounds of downforce and the splitter 234 pounds. In track settings, those numbers rise to 320 pounds and 597 pounds, respectively.
Increasing the downforce involves increasing the angle of attack of the rear wing and removing blanking parts—exactly the same as those used on the Porsche 911 Cup racers—from the splitter. The rear wing doesn’t generate quite as much downforce as that of the GT3 RS. “That’s deliberate,” Preuninger says. “We want to be able to alter the balance of the car front to rear.”
During the car’s development, engineers found steel cables were needed to hold up the front splitter. “The splitter started to sag when we went above 186 mph, throwing the car completely off balance,” Preuninger says. “So we had to attach three steel cables to hold it in place. The force on the splitter—from the airflow and the effect of the low-pressure cell underneath—was more than 440 pounds, and it’s a plastic part. We used nylon cables first, but they kept snapping.”
Tires
The GT2 RS rolls on specially developed Michelin Pilot Sport Cup 2 tires, 265/35 R20 up front, and 325/30 R21 at the rear. Tire development focused on longevity and stability on the track and on improving wet weather grip. “We don’t believe in a ‘qualifying’ strategy, where the tires are good for one or two laps and then fade,” Preuninger says. “That would be very expensive.”
The GT2 RS is electronically limited to 211 mph because of the tires. It will go quicker—220 mph—but Preuninger says a tire homologated to cope with that speed would have resulted in too hard a compound for track use. “For us, top speed is a by-product,” he says. “211 mph is enough. And it reaches this speed very, very quickly.”
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