McLaren's new open-top supercar

McLaren has revealed its sleek MP4-12C Spider - the second in what it says will eventually be a full line of high-performance road going models to rival those of long time F1 adversary, Ferrari.

The new open-top supercar, which will get its first public outing at the Paris motor show in September, joins the recently upgraded MP4-12C coupe in the British car maker's fledgling line-up, with a claimed 0-100kmh time of just 3.1sec and a bouffant rearranging 329kmh top speed.

Clear challenger to the Ferrari 458 Spider, the MP4-12C Spider follows the example of its keenest rival in adopting a retractable hard top that automatically folds and stows within a dedicated well above the engine underneath a tonneau cover aft of the cabin at the push of a switch on its centre console.

Fashioned from lightweight carbon fibre, the MP4-12C Spider's hard top requires 17sec to raise or lower. It can also be operated on the run at speeds up to 30kmh. It was conceived to fold in as small as space as possible without compromising the McLaren's aerodynamic performance.

In all, the new structure and its various electronic components add 40kg to the weight of the fixed roof MP4-12C coupe, taking the new open top model's dry kerb weight to 1376kg in standard guise – some 54kg less than the dry weight Ferrari claims for the 458 Spider.

A steel structure contained in the buttresses behind the seats acts as roll over protection

With the roof raised, the space underneath the carbon fibre tonneau cover otherwise reserved for the hard top can be used as an additional stowage area, with some 52 litres on offer. McLaren will offer its new model with bespoke luggage designed specifically to fit this space.

Power for the MP4-12C Spider hails from the same twin-turbocharged 3.8-itre V8 engine as the MP4-12C. With recent upgrades, the M838T designated unit now delivers an added 12kW over McLaren's original specification engine as used by the MP4-12C coupe up until now, with 460kW arriving at 7500rpm. Torque peaks at 601Nm between 3000 and 7000rpm.

Drive is channeled through a seven-speed double-clutch gearbox to a set of 20-inch rear wheels shod with generously dimensioned 305/30 R20 tyres.

McLaren says its new open top supercar will sprint to 100kmh in exactly the same time as its coupe sibling at 3.1sec. The MP4-1 C Spider is also claimed to crack 200kmh in 9.0sec and run the traditional quarter mile (400 metres) in 9.0sec and 10.8sec - in each case 0.2sec slower than the MP4-12C coupe. Despite its added weight, top speed is down by just 4kmh on its fixed roof sibling at 329kmh.

Ferrari doesn't make any fixed claims for the 458 Spider, saying only that it will accelerate from 0-100kmh in less than 3.4sec and reach a top speed of more than 320kmh.

Since the introduction of MP4-12 C coupe in 2009, McLaren has appointed 38 retail outlets in 23 countries, none of which are in New Zealand.

Sydney Morning Herald