Track-focused roadster snapped at the 'Ring

The rumoured Porsche 718 Boxster Spyder has been spied again, this time doing laps at the Nurburgring.

Developed as an open-top companion to the also-rumoured 718 Cayman GT4, the 718 Boxster Spyder is expected to be the last Boxster with a naturally-aspirated six-cylinder boxer engine, as the company moves toward turbocharging its line-up.

Power in both Cayman and Boxster flagships is said to come from a detuned version of the 4.0-litre flat six used in the current 911 GT3, making around 430hp (321kW) – by comparison, the GT3 makes 500hp (373kW) – but that's all rumours at this stage.

In terms of design, the 718 Boxster Spyder will feature the same fabric roof and pronounced rear flying-buttress treatment as the previous iteration. However, the rear diffuser is meatier than before and the tailpipes appear larger, and have been separated compared to the old version's centre-mounted twin arrangement.

Expect a more aggressive bodykit and aero package – albeit subtle in design to uphold the classic roadster aesthetic – along with an uprated brake, wheel and tyre package.

Previous coverage indicates the 718 Boxster Spyder will come as standard with a six-speed manual, with a seven-speed dual-clutch PDK transmission to be offered as an option.

It's worth noting this prototype looks slightly different to the one spied in January. Key differences include the subtle intake between the front bumper and bonnet, the meatier frontal fascia treatment with larger intakes, different wheels and brake calipers, along with what appears to be larger side skirts.

Timing for the new model is still unknown, though it's believed the Boxster Spyder, and potentially the Cayman GT4, will make their debut sometime later this year.

Stay tuned to CarAdvice for all the latest updates, and click the photos tab for more images.