What would be a birthday without presents? Porsche opted to blow out 70 candles by rolling out a brand-new 911 Speedster concept that fittingly harks back to the first car to the wear the badge — Type 356 ‘No 1’, a low-slung roadster prototype created in 1948 by Ferdinand ‘Ferry’ Porsche.

Although billed for now as a ‘concept’, it’s a dead cert the design study is destined for low-volume production, following in the wheeltracks of the 356 Speedster, as well as subsequent Speedsters based on the 930, 964 and 997 Series 911s. As per its forefathers, the key ingredients of the latest concept (based on 911 Carrera 4 Cabriolet bodywork) is a shorter window frame with a more steeply raked windscreen. Then of course there’s the trademark ‘double-bubble’ humps directly behind the seats. Connecting the two humps at its front extremity is a plexiglass wind deflector with an engraved “70 years of Porsche” logo.

It’s a pure minimalist, with a lightweight tonneau cover in lieu of a full retractable top, and this at least keeps the cabin dry when the car is parked in the rain. Porsche’s boffins aimed to chase every possible gram out of the car, and to this end it makes do without satnav, radio and air-con. What’s more, the bonnet, front wings and rear cover are all made of ultra-light carbon composite. The chassis comes from a GT3, with the whole lot riding on tasty 21in Fuchs rims. Porsche says the flat-six motor delivers “over 500hp” and revs to 9,000rpm, and this means it’s the naturally aspirated GT3 motor, backed by a six-speed manual gearbox.

Don’t read too much into the fuel-filler cap placed in the centre of the bonnet, as that (admittedly cool) design element may be turfed for the production version.