Porsche claims the system can provide up to eight seconds of continuous supply when fully charged, and that it offers a torque vectoring ability to improve agility and steering response. However, in the 911 GT3 R Hybrid, the electric motors can also be used to help reduce fuel consumption, cutting the number of pitstops required or allowing the vehicle to run with less fuel on board.
Read the full story on the Porsche 918 Spyder
The 918 RSR’s construction focuses on keeping the car’s weight to a minimum. As with the original Spyder, its monocoque chassis is made from carbonfibre-reinforced plastic (CFRP). But unlike the Geneva show car, the RSR has a hard-top and doors that open vertically.
It’s widely believed that the shape of the RSR — huge rear wing excepted — is that of the eventual 918 production model. Many of the core features of the 918 Spyder remain, including the deeply scalloped rear bodywork, side-mounted exhausts and air intakes at either side and on top of the rear cowling.
The number carried by the Detroit show car — 22 — pays tribute to a 917 short-tail coupé that won the 1971 Le Mans 24 Hours in the hands of Helmut Marko and Gijs van Lennep. Its distance record — 3315.21 miles at an average speed of 138.13mph — stood until last year’s running of the classic enduro. The car’s colour scheme is a blend of what Porsche calls “liquid metal blue” and the orange commonly used on the firm’s hybrid projects.
Read Autocar's first drive of the Porsche 911 GT3 R Hybrid racer
The cabin features a slice of race-bred purity — the hybrid flywheel replaces the passenger seat — but it still looks realistic and luxurious enough to give a strong hint at the eventual 918 production car’s interior.
The fascia and centre console look plusher and less extreme than in the original concept, with a mixture of bare aluminium and brown leather. Porsche claims that the second of these materials “cites the history of the gentleman driver”.
The Spyder’s touch-sensitive control interface has been replaced by a simpler set-up with rocker switches, and there are now gearshift indicator lights integrated into the leather-clad steering wheel. There’s also a display to inform the driver of the current charge levels in the brake energy recuperation system.
Read more on Porsche's Detroit show star
The RSR’s appearance at Detroit is part of a carefully phased introduction of a hybrid ‘halo’ car by Porsche. Like the 911 GT3 R Hybrid before it, the new racer is now set to be used as a testbed for the hybrid systems in motorsport. An appearance at the Nürburgring 24 Hours in the summer is considered extremely likely. On its debut in the race last year, the 911 GT3 R Hybrid led for more than eight hours.
Porsche could then wheel out the production version of the car in early 2012. It is unlikely to rush it out by this autumn, preferring to further develop the hybrid systems and avoid overshadowing the arrival of the next-generation 911 at September’s Frankfurt motor show. The company has taken letters of intent and deposits for the car, even though the final price — expected to top €500,000 (£422,000) — has yet to be confirmed.
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