What is it?
A one-of-600 hit of pure 911 adrenaline. The regular GT3 RS is an intoxicating, intense driving experience itself, but this limited run, 4.0-litre version is even more so. Boasting greater power and even less weight it's about as intimate a 911 driving experience you'll ever get. It's about as close as a race car for the road as you'll get too, yet it's not as compromised as you might think as a result.
Is it any good?
The 'standard' 3.8-litre GT3 RS is sensational, as is its non-RS GT3 sibling, so the GT3 RS 4.0 comes from a proven bloodline. Porsche has done what it does best and made lots of small but significant changes to up the performance and decrease the weight. The kerb weight drops by 10kg thanks to lighter polycarbonate windows, carpets and carbon fibre front wings and bonnet. The mechanical changes all relate to the 4.0's racing RSR relative, the engine's increased capacity thanks to the racer's crankshaft, while other internal revisions in titanium allow the 50bhp increase in power to 493bhp. The torque's increased too, it adding to the engine's mid-range flexibility without robbing it of its highly entertaining high-rev intensity.
Unsurprisingly it's fast. Devilishly so, with 62mph arriving in just 3.9 seconds. Third gear will see the wrong side of 90mph. The crushing ease by which the RS 4.0 piles on the power is incredible. There's no obvious let up in its acceleration, at least not on the road. On track the RS will shine, the enhanced aerodynamics (a steeper angle of attack on the rear spoiler and front-end controlling air 'flics') helping the RS manage and utilise the air rushing by it. The suspension has been fettled too, with the rear lower mounts rose-jointed for greater precision. The way the RS rides on even our lumpy, bumpy roads is very impressive given its obvious focus.
It's the interaction that makes the driving experience so intoxicating though. There's little that can deliver the same sort of urgency mixed with a feeling of control. The steering is rich in its weighting, the clarity and level of communication from the wheel's rim allowing the driver to really exploit the RS's potential. For something so rapid and so single-minded it's never intimidating, its responses so faithful to your input you'll never tire of driving it. Simple pleasures like the mechanical action of the six-speed gearshift, the purity of the steering, the immediate, seat-belt testing braking power and the sound of that 4.0-litre engine being worked hard behind you add up one of the most enjoyable driving experiences money can buy.
Should I call the bank manager?
With just 600 being built you're probably too late. To get your hands on one you'll be known to Porsche and more than likely purchased your fair share of GT3 and RS models previously. The £128,466 price tag is unlikely to trouble you then. That's a pretty rock solid investment, as the 4.0's status as the ultimate RS means it's already a bona fide classic. To that hefty list price (£20k more than the standard RS) you might want to add some more money for PCCB ceramic composite brakes and a lithium-ion lightweight battery, both fitting in nicely with the RS's lightweight, ultimate racer focus.
The added flexibility of the 4.0-litre engine allied to the added kudos of having a limited-run ultimate RS is certain to project the RS 4.0 into the stratosphere as a must-have model for Porsche's most discerning customers. The changes undeniably add up to a greater whole, but for all but the most demanding drivers the standard RS isn't going to leave them wanting for more. For the handful with the means and access to it the 4.0 is sensational, though we're not so sure about the stickers...