First look: Porsche reveals its ultimate street racer

UP TO 10 examples of the most extreme street-legal Porsche racecar, powered by the largest engine to grace the rear-end of a factory 911, will become available in Australia late this year, each priced at more than $400,000.

The special-edition Porsche 911 GT3 RS 4.0 Coupe will be limited to a production run of just 600 units globally as a swansong for the current-generation 997-series 911.

While the all-new, and even more confusingly named, 991-series 911 will make its world debut at this September’s Frankfurt motor show before going on sale in Australia next year, the RS 4.0 is the ultimate naturally aspirated 911 road car.

Taking the relatively new GT3 RS Coupe to even greater extremes, the 4.0 – as its name suggests – employs a variation of the 4.0-litre boxer six from the 911 GT3 RSR racer to deliver an astonishing 368kW (500hp) at a heady 8250rpm (350rpm higher than the GT3 RS’s 3.8-litre flat six) and some 460Nm of peak torque 1000rpm earlier at 5750rpm.

Borrowing the RSR’s crankshaft, forged pistons and titanium conrods not only makes the Porsche Motorsport-developed flat six the most powerful naturally aspirated 911 engine ever, but gives the RS 4.0 a specific output of some 92kW per litre, which at 125hp/litre easily breaks the magic 100hp/litre mark once achieved by few road cars.

The wildest GT3 road car’s 368kW output betters the ‘garden variety’ GT3 (320kW/430Nm) and piping-hot GT3 RS (331kW/430Nm), and even matches the peak power – but not torque – of the force-fed flat-six in the 911 Turbo and the twin-turbo V8 that powers the Cayenne and Panamera Turbo models.

Porsche says the close-ratio six-speed manual-only GT3 RS 4.0 is almost as quick as the 911 Turbo too, with claimed 0-100km/h and 0-200km/h acceleration of just 3.9 and 12.0 seconds respectively, depending on its (variable) gearing.

Perhaps more importantly, with lightweight racing suspension components, carbon-fibre sports bucket seats, bonnet and front guards, a plastic rear window and “weight-optimised” carpet limited the two-seater’s kerb weight to just 1360kg with a full tank of fuel, Porsche says the RS 4.0 can lap Germany’s famed 20.8km Nürburgring-Nordschleife road course in just seven minutes and 27 seconds – down from 7:33 for the GT3 RS it replaces on the Zuffenhausen production line.

While Porsche stresses this is not a final figure, that is already more than 10 seconds quicker than the comfort-oriented 911 Turbo (7:38) and less than 10 seconds slower than Porsche greatest Nurburgring performer, the 911 GT2 RS (7:18).

It also betters the 7:32 time of the ‘standard’ twin-turbo rear-drive GT2 RS and falls only three seconds short of Nissan’s giant-killing GT-R (7:24), which infamously battled with Porsche for top Nurburgring production car honours last year.

That sort of pace doesn’t come cheap, however, with the RS 4.0’s $409,100 pricetag being higher than the ‘standard’ GT3 RS sticker price ($341,100) by a staggering $68,000.

The purest 911 road car ever produced also eclipses the price of every other Porsche model – including all Panameras and Cayennes – except the 911 Turbo S Coupe ($423,300) and Cabriolet ($442,800) and range-topping 911 GT2 RS ($560,000).

All examples are painted white with red bonnet, roof, mirrors and body-side pin-striping to “emphasise its dynamic stance and link to 911 racing cars” and are also differentiated from lesser 911s by “precision aerodynamic engineering” headlined by new lateral front air deflector vanes that make their production debut on the last 997-generation 911.

Dubbed “flics”, Porsche says they increase front downforce and, combined with large, steeply inclined rear wing with side plates, create positive rear downforce of 190kg at top speed.

Naturally, the RS 4.0 also features even wider wheel tracks and lower ride height, with additional ball-joint and a revised versions of Porsche’s Active Suspension Management system bringing the GT3 RS 4.0 closer to the set-up of the wild GT2 RS than the regular GT3 RS.