Laying eyes on the 918’s evocative styling puts an emphatic end to any argument about the car’s intended stature. Rather than be slavishly functional, the shape of the car’s carbonfibre-reinforced plastic bodywork pays homage to just about every important racing Porsche of the past half century. The 917, 935, 906, RS Spyder – all are acknowledged in places. You don’t do justice to cars like that by setting out with qualified commitment to the performance cause.

Neither is this car the product of lesser ambition. It may weigh almost 200kg more than a McLaren P1 – 1740kg on MIRA’s scales – but its lithium-ion battery is twice the size of the P1’s (6.8kWh), its electric motors supply much more propulsive assistance, and the car has 50 per cent more overall torque.

Nic Cackett

Nic Cackett

Road tester
There's no option on wheel sizes – it's 20 inches on the front and 21 inches on the rear by default

The 918’s underbody consists of a stressed monocoque tub and attached engine carrier subframe made entirely of carbonfibre-reinforced plastic. The body panels and doors are CFRP, too, the bumpers flexible polyurethane. So the car is both necessarily heavy but about as light as it could possibly be.

The suspension and engine are both adapted from what you’ll find in Porsche’s 2005 RS Spyder race car. That means a 4.6-litre V8 made of aluminium, titanium and steel is mounted midships, developing 599bhp, revving to more than 9000rpm and weighing just 135kg.

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Suspension is by forged aluminium wishbones and links, with PASM adaptive dampers as standard. The electro-mechanical rear-steer system from the ‘997’ GT3 also features.

The electrified portion of the car’s propulsion system, meanwhile, consists of one permanently excited electric motor per axle, producing a maximum 282bhp and 431lb ft of torque between them. While the rear motor-generator drives through the same PDK transmission as the combustion engine, the front motor drives via a single speed and is deliberately under-geared to run out of revs and decouple at 165mph. But not before it has contributed to the crankshaft-equivalent of 944lb ft of peak torque, as well as 874bhp at 8500rpm. Top speed is 214mph. EU-tested CO2 emissions are 70g/km.

The 918, then, probably has more power than a 2015 Honda-engined F1 car, and yet it emits less CO2 than a Honda Insight economy saloon.

Also offered is the Weissach Pack. Adding 10 per cent to the price of a £780k hypercar for a weight-saving options package made up primarily of deletions from the car’s standard equipment looks, on the face of it, like profiteering. But Porsche has learned from the criticism that it received about the Cayman R and will allow you to pick and choose the bits you want to keep and to remove from your 918 if you do commit to the Weissach Pack.

And there aren’t only deletions but also glorious substitutions to consider. Ceramic wheel bearings save only 700g over steel ones but you’ll want them once you know they’re on offer. Magnesium alloy wheels are the biggest individual weight saving on the list (14.9kg). Among the smallest are carbonfibre shift paddles (200g) and leather loop interior door openers (200g).

But it’s the sense that Porsche has left no stone unturned in saving mass — 41kg in all — that really convinces. How many other supercars have a carbonfibre-reinforced plastic bonnet stay, after all? And how many other supercar makers would tell you that it’s worth 500g in place of the normal one?

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