IT’S hard to believe it is almost seven years since Porsche broke the iconic 911 mould when it delivered the first liquid cooled version of its famed rear-engined coupe to Australia in January 1998.

Quicker, faster, safer, more civilised and easier to drive than the more raucous 993, the 996-series quickly became the most popular 911 ever. But still Porsche purists bleated it had lost the look, feel and soul that helped establish 911’s automotive legend status.

Now Porsche attempts to cover both bases with the redesigned 997 series, which – although a far more evolutionary design than the ground-breaking 996 - succeeds in presenting a more classic shape while improving the 911 breed in almost every tangible way.

When the new 911 goes on sale here on October 1, it will for the first time since 1977 be available in two Carrera variants from launch.

But the marginally more powerful base model and its significantly higher-performing Carrera S sibling also bring a host of suspension, braking, safety, seating, body strengthening and aesthetic advances.

The final product is said to follow five years of development, 1,500,000km of testing, 887 CAD hours, 357 design sketch rejections and work by 698 staff.

The most noticeable change for a 911 that Porsche claims is 80 per cent new is the revised bodyshell, which carries over the 996 roof but still appears more closely related to 993 than 996.

Further differentiated from Boxster, the new shape is more slippery and employs extra underbody panelling to drop its aerodynamic Cd factor from 0.30 to 0.28 (with the wider-wheeled Carrera S at 0.29).

Deeper front and rear bumpers, flat door sides, more pronounced wheel arches and 38mm wider rear haunches give 997 (now with a total width of 1808mm) a more traditional 911 look that cohesively combines frontal elements of the Carrera GT flagship with round, 993-style headlights and a rear-end that’s only 20mm narrower than the wide-bodied 911 Turbo.

Subtle new design cues like a different engine cover cum extending rear spoiler and twin-arm mirrors become apparent only on closer inspection, while overall length at 4427mm is just 3mm shorter than 996, which was a substantial 185mm longer than the smaller-cabined 993.

The 997 interior looks to 911’s past too, continuing with a revised iteration of 996’s overlapping instrument panel but eschewing many of the associated circular design themes that made the previous 911 interior so uniquely beautiful.

Straight lines now prevail in a return to the more technical look presented by 70s and 80s 911s, and while twin cupholders will appease the US market and a lift in material quality addresses some of the complaints levelled at 996, overall the 997 interior is more functional but less pretty.

And there is no change to the kids-only zone out back, where the twin folding rear seatbacks are still vertical and legroom remains almost non-existent. New 911 drivers, however, do gain 12mm more stretching space thanks to seats that are lower and pedals that are further away. Boot volume increases by five litres to 135 litres.

But performance is what 911 is all about and 997 raises the bar again. While much new technology remains optional and Carrera S benefits more in terms of power, both 911 variants are based on a chassis that features a 21mm wider front track (1486mm), 54mm wider rear track (1534mm) and, for the first time, a variable-ratio steering rack that increases turning force as lock is wound on.

As a result, 911’s turning circle has increased from 10.6 to 10.9 metres and turns from lock to lock reduced from 2.98 to 2.62.

Both Carreras also feature an extra two airbags, bringing the total number to six with the addition of door-mounted head airbags to the current model’s twin front and side airbags. Further increasing 911 active safety armoury is the fitment of Porsche Stability Management, which was previously standard only in 911 Turbo and C4S.

The common bodyshell itself offers 40 per cent more flexural and eight per cent more torsional rigidity than the greatly stiffened 996, courtesy of extra boron steel strengthening beams in the 997 firewall, roof, doors and floor.

Along with extra equipment, this adds 25kg in total weight to 911 Carrera (now 1395kg), while Carrera S is 50kg heavier than 996 Carrera at 1420kg and weight distribution remains 38/62 per cent front/rear.

Offsetting the extra weight is more engine performance for both 911 variants. The basic Carrera continues with the 996 911’s 3.596-litre six-cylinder boxer engine with the same 370Nm of torque at 4250rpm but 4kW more peak power with 239kW now available at the same 6800rpm. This means 911 Carrera’s 0-100km/h acceleration remains a claimed five seconds dead (5.5 for the auto) and top speed remains 285km/h (280km/h auto).

For Carrera S there’s a new bored and stroked, 3.824-litre version of the flat six - giving it the largest capacity yet for a standard 911 – which features a higher 11.8:1 (instead of 11.3:1) compression ratio to produce 261kW at 6600rpm and 400Nm at a higher 4600rpm. Average fuel consumption is unchanged at 11.0 litres per 100km (11.2 auto), while both engines get a more powerful 2100-watt alternator and major service intervals increase by 10,000km to a lazy 30,000km.

The extra Carrera S oomph drives it to 100km/h in 4.8 seconds (5.3 auto) and to a claimed top speed of 293km/h (285km/h auto). Earning it the status of interim 997 GT3, Carrera S approaches the performance of the current GT3 and Porsche’s tradition of understating performance figures would suggest the S is the first 911 Carrera to be good for a genuine 300km/h top speed, or almost lineball with the current 911 Turbo’s claimed top speed.

In fact, Porsche claims Carrera S laps Nurburgring’s northern circuit a whole 20 seconds faster than the current 911 Carrera. Average fuel consumption rises to 11.5L/100km (11.7 auto).

To cope with the extra engine output, the 911 six-speed Getrag manual has been replaced with a 15 per cent shorter-throw Aisin six-speed manual with lower internal ratios but the same final drive, while the Tiptronic semi-auto option features carries over its ratios but comes with lower final drive gearing. Carrera S manual adds a self-adjusting clutch.

Carrera comes with 18 x 8.0-inch front wheels with larger diameter 235/40-section tyres and 18 x 10-inch rear wheels with 265/40 tyres, but Carrera S gains 19 x 8.0 front wheels with 235/35 tyres and 19 x 11-inch rear wheels with 295/30 tyres.

Similarly, Carrera continues with cross-drilled 318 x 28mm front and 299 x 24mm rear brake discs, each with four-piston black monobloc Brembo callipers. Carrera S, however, adds 911 Turbo-style 330mm brake rotors (34mm thick up front, 28mm at rear) and larger, reinforced red callipers. Carrera S also rides on 10mm lower suspension.

Both variants are now available with 911 Turbo’s Porsche Ceramic Composite Brakes, which feature yellow six-piston front callipers. The PCCB system is the most expensive 997 option at a whopping $18,990, while other new technology includes Porsche Active Suspension Management (PASM - $4490), which selectively (via a push-button) or automatically chooses between sporting or comfortable damping settings.

The final major technology advance – again optional, this time at $2190 – is Sport Chrono Package Plus, which features a dash-mounted analogue lap timer that records and presents its results graphically on the monitor via the Porsche Communication Management system.

More practically, it also features a BMW-style sport button that makes the accelerator pedal control map more aggressive, increases the stability control system’s intervention level and controls the PASM and Tiptronic map control curves.

Along with bigger brakes and wheels and more power, Carrera S also features sports seats with the same 12-way power adjustment, and adds silver instruments, bi-Xenon headlights with washers and quad exhaust outlets.

Sports suspension (20mm lower and including a rear diff lock) costs $4490, while other 997 options include metallic paint ($2590), rear park assist ($1590), tyre pressure monitoring system ($1790), full leather seats ($3490) and the new adaptive sports seats ($3950).

At $195,225 (up from $187,600), Porsche says the basic 997 911 Carrera manual adds $15,950 more value for half the price increase. Carrera Tiptronic is priced at $203,225, while the new Carrera S variant carries a $221,100 sticker price. The Carrera S auto carries the same $8000 premium at $229,100.