The controversial new Porsche 991 GT3

The Porsche GT3 has always been the benchmark for driving enthusiasts when it comes to track cars.  This 991 iteration has been keenly anticipated especially as for the first time, it uses a PDK system. Gone is the manual gearbox, much to the dismay of many loyal Porsche fanatics. It looks familiar, aping the look of the previous four GT3s we’ve known and loved, but the evolutionary skin hides some revolution underneath.

A new engine sits behind the rear axle, the famed Mezger Six of previous GT3s replaced with a 25kg-lighter direct injection 3.8-litre flat-six. It’s loosely related to the 394bhp unit in the 911 Carrera S, but is gets a dry sump and forged titanium components. It’s rated at 468bhp and 325lb ft; figures up from the 997.2 GT3’s 429bhp and 317lb ft, with peak power served 650rpm higher, at a heady 8250rpm. Top speed rises by 2mph to 196mph, while 0-62mph drops by a huge 0.7sec to 3.5sec.

Some of that drop can be attributed to perhaps the GT3’s biggest talking point, its standard seven-speed PDK twin-clutch transmission. Porsche claims similar reactions to the 911 GT3 Cup cars, with gearchanges executed in less than 100 milliseconds. It comes with shorter gear ratios than other Porsche PDK applications, while there’s a manual declutching feature when the driver simultaneously pulls both paddles. The gearstick, when used sequentially, offers a motorsport style back-for-upshift, forward-for-downshift layout.

Another new 911 GT3 feature is rear-wheel steering. Below 30mph the rear wheels turn in the opposing direction to the front wheels, improving manoeuvrability, while above 50mph they turn in the same direction, improving stability. Porsche reckons this new technology played a big role in reducing the GT3’s Nurburgring Nordschleife laptime to below 7min30sec.

The new 911 GT3 gets an all-aluminium chassis based on the 911 Carrera’s, but rides 30mm lower. Porsche’s PASM variable dampers are standard fit, while the GT3 gets its own multi-link rear axle design. Among the other standard equipment is Porsche Torque Vectoring Plus (including a locking rear differential) and 20in centre-locking alloy wheels, an inch-bigger version of the GT3 staple.

Despite a host of weight-saving measures – including a hollow subframe and aluminium exterior parts – the new GT3’s claimed DIN weight of 1430kg is 35kg heavier than its predecessor’s, the new gearbox and four-wheel steering likely contributing factors.

[Source] http://www.evo.co.uk/