New Engine Powers Porsche 718 Spyder, 718 Cayman GT4

Porsche chooses naturally aspirated 6-cyl. power for two hardcore additions to its existing 718 Boxster and 718 Cayman lineups: the 718 Spyder and 718 Cayman GT4.

Planned for North American delivery by the end of 2019, both models feature a new mid-mounted 4.0L horizontally opposed engine that forms part of latest 6-cyl. engine family known internally at Porsche as the 9A2 Evo, the German automaker confirms.

Based on the turbocharged 3.0L unit used by the 911, the new naturally aspirated 6-cyl. was chosen over a more highly tuned version of the turbocharged 2.5L 4-cyl. found in the 718 Boxster GTS and Cayman GTS.

With 414 hp, the new engine develops 44 hp and 35 hp more than the earlier naturally aspirated 3.8L horizontally opposed 6-cyl. that powered the previous 718 Boxster Spyder and 718 Cayman GT4. It also revs to 8,000 rpm and delivers peak torque of 310 lb.-ft. (420 Nm) on a band of revs between 5,000 rpm and 6,800 rpm.

New technology increases the engine’s efficiency without the need for forced induction. Included is a new adaptive cylinder-control system that can momentarily pause fuel injection in one of the two cylinder banks under partial loading in a cylinder shutdown process. Piezo injectors are used for the first time alongside a variable intake system and Porsche also provides its latest in a distinguished line of naturally aspirated units with a particulate filter to reduce NOx emissions.

Both new Porsche models channel their power through a standard 6-speed manual gearbox and locking differential to the rear wheels.

The result is an official 0-62 mph (100 km/h) time of 4.4 seconds, with the 718 Spyder managing a top speed of 187 mph (301 km/h) and the 718 Cayman GT4 topping out at 188 mph (303 km/h). Porsche also claims combined-cycle fuel consumption of 21.6 mpg (10.9 L/100 km) on the WLTP test cycle.

A complete rethink of the aerodynamic packages on the new Boxster and Cayman models sees the 718 Spyder adopt a new manually operated roof, which Porsche says can be stowed in “just a few steps.” Also included on the new open-top is a rear spoiler that deploys at a speed of 74 mph (119 km/h) and rear diffuser element to increase downforce.

Changes to the body of the 718 Cayman GT4 are said to produce up to 50% more downforce than the preceding model with no increase in drag. The rear wing (below, left) alone is claimed to be 20% more efficient than that used by the old Cayman GT4, developing an added 26 lbs. (12 kg) of downforce on the rear axle at 124 mph (200 km/h).

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Porsche says the new aerodynamic package, chassis alterations and extra power enable the 718 Cayman GT4 to lap the 12.8-mile- (20.6-km-) long Nürburgring Nordschleife circuit in Germany more than 10 seconds quicker than its predecessor.

In the U.S., the 718 Spyder is priced at $96,300, while the 718 Cayman GT4 wears a $99,200 price tag, both excluding a $1,250 destination charge.

The 718 Cayman GT4 has the option of a Clubsport package in selected markets, though it is not planned to be offered in North America. This includes a steel roll bar at the rear of the cabin, a fire extinguisher and a 6-point seatbelt for the driver’s seat.