What we’ve learnt from the Porsche 991: performance
My current predicament is akin to automotive perfection: piloting an exquisitely-optioned Guards red 991 Carrera GTS, I’m steering it through every sweeping bend down Ireland’s Wild Atlantic Way, the majestic North Atlantic Ocean lapping the shores to my right, with realms of unspoilt Irish countryside rolling gloriously to my left.
Ireland’s West Coast has certainly dealt me a good hand here. Largely untapped as a ‘great driving road‘ to the majority of motoring enthusiasts, the Wild Atlantic Way is bereft of traffic (all 2,500kilometres of it!) and provides one of the very best settings in Europe to put a 911 to the test.
And that’s exactly why I’m here. See, the current generation of Porsche 911 is to be replaced at the end of summer and so, after some four years under the bright lights of showrooms, it’s high time we took stock of the 991 and investigated what we’ve learned from the all-new sports car on the road. In parts two and three later this week we’ll look at the 991’s chassis and driving experience respectively, but in this first instalment it’s the performance of Zuffenhausen’s latest icon that’s in for some Total 911 scrutiny.
Since its inception in 2011, the 991-generation has been powered by a DFI-iteration of the famous Porsche flat-six, itself an evolution of the unit found past the rear axle of the previous 997. The switch to DFI engines has been for good reason: they are more efficient, improving both performance capabilities and emissions.
The 991’s DFI unit has proven as refined as it is versatile, with iterations of the same engine powering the entire 911 lineup through the naturally aspirated Carrera, GT3 and GT3 RS, as well as the Turbo with variable turbine geometry. This is a feat the 911 hasn’t accomplished for more than two decades – and performance hasn’t been compromised here either, the 9A1 unit pleasingly retaining that delightfully peaky character that has been a hallmark of the 911 for more than 50 years.
However, the biggest evolution in Porsche 911 performance has in fact come from the device charged with transmitting power from Porsche’s latest flat six to the wheels. With economy chiefly in mind, the 991 has had a seven-speed gearbox mated to its 9A1 engine, available as a conventional manual or, for £2,817 extra, in automatic PDK guise.
The Porsche Doppelkupplung unit is wonderfully refined: fitted here to the GTS, gear changes take milliseconds and, more importantly, the system is infinitely more intelligent than the one fitted to the previous-generation 997. With some 300 different map options programmed into the gearbox, PDK is constantly able to adapt to your driving style, holding on to gears under spirited driving and changing up on time when meandering through town.
While the system isn’t quite perfect (changing down a gear in ‘manual’ mode still sends an awkward shunt through the car, though it’s light years ahead of the same elongated sensation evident in 993 Tiptronic ‘boxes), capabilities of the technology are keenly demonstrated in the GT3, where shifts are sharper and smoother still. Porsche’s double-clutch gearbox is a revelation on the latest era of 911 and it’s no wonder more than 50% of current 991 orders have featured PDK on the options list.
The caveat here is the manual seven-speed gearbox, which has come in for due criticism from Total 911 over the last four years. Unduly clunky to operate (particularly on all-wheel-drive 911 variants), the throw between gates was messy at best and really detracted from the driving thrill of having a third pedal for the driver to work with.
We’ve previously speculated whether this was a deliberate move from Zuffenhausen to point customers in the direction of the PDK unit, but Porsche eventually relented to the criticism and revisited the gearbox in time for the Carrera GTS launch, which is now much more fluid between gates – exactly as it should always have been. Indeed it took the full four years of 991 evolution but finally Porsche have a manual gearbox in their latest 911 worth shouting about, and so wether you opt for a manual or PDK 991, you’re well placed to unlock the full potential of that brilliant DFI flat six. Just how you go about unlocking that brilliant 911 performance is down to your talent and driving style, of course…