► Porsche readies four-cylinder boxers

► 981.2 updates for Boxster, Cayman

► Cayman repositioned below soft-top

The trickle of turbocharged Porsches will become a flood in 2016, when the smallest and cheapest sports cars - the Boxster and Cayman duo - adopt an all-turbo engine line-up. Our latest spy photos capture the new roadster on the roads near the Stuttgart factory and museum in a state of undress; barring a transit protection wrapper and headlamp camo, it is virtually undisguised.

We’ve previously reported on the small-capacity boxer four-cylinder engines coming to the junior Porsches, and in the new August 2015 issue of CAR magazine we reveal further details about the upcoming four-pots:

Boxster/Cayman 240bhp 2.0-litre flat four turbo

240bhp 2.0-litre flat four turbo Boxster S/Cayman S 300bhp 2.5-litre flat four turbo

300bhp 2.5-litre flat four turbo Boxster GTS/Cayman GTS 370bhp 2.5-litre flat four turbo

The advanced direct-injection engines are believed to make do with only one fixed-vane turbocharger, but Stuttgart is planning an e-boost electric system as a short-to-mid-term option. The new four-pots spell the end of the boxer six-cylinder in mainstream Boxsters and Caymans, although specials like the GT4 will continue with the extra cylinders, CAR understands.

When will we see the new 981.2 Boxster and Cayman twins?

Not until early 2016, according to our sources. That points to a motor show debut at Detroit or Geneva next spring, we reckon. Like the facelifted, all-turbo 911 range, due at the 20105 Frankfurt motor show, the revised two-seaters are set to receive a truckload of chip-controlled safety and convenience upgrades. But the key innovation is of course the pair of brand-new horizontally opposed four-cylinder engines. It might even be enough to warrant a new badge; we hear the 717 name being bandied around, aligning the sports cars with big brother the 911.

Cayman to be repositioned beneath Boxster

CAR understands that the 981.2 relaunch will also include the option, in some markets, to position the Cayman as the entry-level, cheaper model for the first time. The move is designed to increase awareness and boost sales; the soft-top has consistently out-sold the coupe ever since launch a decade ago. Should Porsche do this and risk annoying existing customers? Let us know in the comments below.

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