2016 Porsche 718 Boxster - first ride

What we know today is that there will be two types of turbocharged flat four available for the new Boxster, both developed from the new turbocharged flat six engine (codenamed 9A2B6T) created for the recently facelifted 991-generation 911.

In essence, Porsche has got rid of two cylinders in order to create the new turbocharged flat four (codenamed 9A2B4T). The base 2.0-litre boxer unit has a single turbo and is expected to make around 295bhp and 258lb ft. This engine’s bore and stroke dimensions are 91mm and 76.4mm respectively and these, as well as the cylinder pitch, are the same as the 911’s.

The Boxster S will have a larger bore and stroke than the base model, increasing engine capacity to 2.4 or 2.5 litres and making around 355bhp and 295lb ft. The rumour is that a turbocharger with Porsche’s Variable Turbine Geometry (VTG), as used by the 911 Turbo, will be fitted to this engine.

Matthias Hofstetter, the man in charge of powertrain development for the Boxster and Cayman, proudly explains how they could successfully fit a turbocharger into a space as the tight as the Boxster’s engine bay. “Engine packaging was one of the most difficult parts of development,” he says. “The two front cylinders were replaced with a turbo unit.

The intercooler layout was also a pretty tough task. Facing forward, air coming from the left side air intake flows into a water-cooled intercooler. It reduces the turbocharged air from 160deg C to 50deg C. We call this a Lower Temperature Intercooler System.”

Another challenge was vibration control. “A 
flat four is an inherently well-balanced engine,” says Hofstetter. “To achieve the smoothness 
like a six-cylinder engine, four active engine mounts were installed. We believe this is a very effective solution. Fuel efficiency, which is the 
most important factor of the downsizing, is improved by one litre per 100km [around 5mpg] compared to the current model.”

His confidence as an engineer, and relief after such an accomplishment, is palpable, and the figures are borne out during our test. From the passenger seat, a look at the rev counter reveals that the 2.0-litre flat four is running stress-free 
to 7400rpm, right below the redline.

As a result of the additional parts needed for the turbo system, the overall weight of the base Boxster has increased from 1315kg to 1400kg. Top speed is nonetheless more than 174mph and the 0-62mph sprint takes a claimed 5.5sec. The Boxster S hits 62mph in just 5.0sec.

Our first look at the car doesn’t reveal much in the way of exterior changes, but examine it more closely and you can see upgrades such as newly shaped wings, side panel air intakes and rear spoiler. Inside, the materials, feel and finish are improved to an astonishing degree. You’ll be able to order an optional 918 Spyder-style steering wheel, too. On cars equipped with a PDK dual-clutch automatic gearbox, there will also be a Sport Response button that primes the drivetrain for maximum response for about 20 seconds at a time.