First your ribs must collapse in on themselves so that your hips are able to touch your shoulders. Then, in one smooth movement, sink bum-first into the seat before inverting your shoulders so that they fit between the narrow backrest and, finally, collapse your head flat across your torso. Hey presto, you're in.
Welcome to the wonderful world of 911 convertibles, a land first visited with the 911SC 30 years ago. It's a formula that shouldn't work - the 911's rear-engined configuration has always made it a sports car with an edge, which in a coupé makes sense. Chop the roof off and what you're left with is a slightly wobbly edge, like a tent that's missing a pole.
Realising that people don't buy £80,000 convertibles for a seat of the pants driving experience, Porsche has built the latest 911 drop-top with a wider audience in mind - an audience in search of a car that's comfortable and cossetting, with a good slug of power and a killer exhaust note. This is a 911 designed to appeal to the kind of people who would otherwise buy a Mercedes or BMW.
In order to facilitate this the latest 991 version of the 911 is 2in longer than the model it replaces, with a wheelbase stretched by 4in and front track widened by 2in. Its roof is a completely new "panel bow" design consisting of two fabric-covered magnesium panels and a glass rear screen that forms a completely rigid surface when the roof is in place. Lower it, which takes 13sec and can be done at speeds up to 31mph, and the panels sit on top of each other in a Z-pattern in a compartment behind the rear seats.
Opening and closing the roof is done via a switch located where logic says the new electronic handbrake should be, so don't be surprised if you start to see 911 owners searching for their car on the hill where they parked it and the car itself in a hedge at the bottom of the hill with its roof ajar.
With the roof stowed, the 911 looks slightly ill-proportioned, with a sleek nose at one end and a massive bum at the other. It's not unattractive, but neither is it classically beautiful. What that panel bow system does mean, though, is that as well as being lighter than the old fabric roof, it also retains the exact silhouette of the coupé when raised. With the roof up a new type of insulation also ensures that the 991 is about as refined as soft tops come.
As with the recent Porsche 911 coupé, the interior of the Cabriolet is based on that of the Panamera GT car. This means slightly more space, excellent quality, lots of buttons peppered across the dash and transmission tunnel, and more electronic gadgets than you can shake an iPad at. This is a 911 with heated and cooled seats and a satnav whose directions can be shown not only on the main screen but also in a cowled dial alongside the rev counter. There are also the ultimate in open air accessories; a heated steering wheel and an electronically deployed wind deflector.
Engine choices are as per the coupé, so a direct injection petrol flat-six in 3.4-litre 345bhp Carrera or 3.8-litre 395bhp Carrera S specification, both of which are available with seven-speed manual or PDK twin-clutch transmissions and auto stop/start as standard.
Twist the key and the flat-six fires up with a bark, while the springy clutch and perfectly weighted throttle are classic 911. The manual gearbox is less of a success, its seven forward rations meaning you spend too much time somewhere in the mix of third, fourth, fifth and sixth gears, but are never really sure where.
In a bid to reduce weight and maximise efficiency, the 911's hydraulic power steering has also made way for Porsche's electro-mechanical system, which has lost the classic 911 slightly grainy feel in favour of perfectly consistent weighting. It's one of several detail changes that help this new 911 to be about 15 per cent more economical than the one it replaces, but also makes it feel more accessible to people used to the steering of something like a BMW 6-series or Mercedes SL.
The slightly longer wheelbase also means the 911 rides nicely for a car of this type, with firm but well controlled damping and an incredibly stiff bodyshell. Forget any notion of scuttle shake - the only time you'll ever know it's a convertible is through very fast corners when you can sense just a tiny amount of flex as the rear tries to catch up with what the front is doing.
With either engine it's flipping fast, particularly above 4,000rpm, and it makes all the right noises too, from bellows and wails to enough pops and crackles when you lift off the throttle to make you wonder if somebody has secreted some Rice Krispies up the exhaust. That wind deflector cuts barnet buffeting to a minimum too, although generates a fair bit of noise as it does so.
As for which model to choose, you can feel every one of the extra 50 horsepower in the Carrera S, but in truth there's only so fast you'd ever need to go on the public road and 0-62mph in 5.0sec and a 178mph top speed do the job. So we'd take the Carrera and save the £10,000 price difference.
Whichever model you choose, this new Porsche 911 Cabriolet is, in almost every area, a better car than the one it replaces. It's faster, more stable, more refined, more economical... and yet one can't help feeling that in making the 911 into such a competent all-rounder, a bit of the old magic has been lost.
It's like asking Raymond Blanc to cook you a sirloin steak and then insisting that it's well done and covered in Ketchup. It might appeal to more people, but that doesn't mean it's better.
THE FACTS : Porsche 991 Carrera Cabriolet
Tested: 3,436cc flat-six petrol engine, seven-speed manual gearbox, rear-wheel drive
Price/on sale: from £79,947/March 3
Power/torque: 345bhp @ 7,400rpm/ 288lb ft @ 5,600rpm
Top speed: 178mph
Acceleration: 0-62mph in 5.0sec
Fuel economy: 30.7mpg (EU Combined)
CO2 emissions: 217g/km (198g/km with PDK gearbox)
VED band: K (£580 for first year, £260 thereafter)
Verdict: There is an argument that the latest 911 Cabriolet is becoming more GT than sports car, but it's still a mighty fine machine that will give BMW, Mercedes and Jaguar serious food for thought
Telegraph rating: Four out of five stars
By Chris Knapman, The Telegraph
