McLaren has released a new video showcasing its 675LT 'LongTail' on track. The new supercar - which is designed to be a harder, lighter and more powerful version of the 650S - made its debut at the Geneva motor show in March.

Already on sale, the 675LT is priced at £259,500 - around £64,000 more than the 650S on which it is based. Just 500 examples will be made - but all planned models are already sold.

Many of the 675 LTs will have gone to existing McLaren owners, including many who buy every model from the company that is offered to them.

The coupé-only 675LT - ‘LT’ refers to its long-tail aerodynamic design, something first used on the 1997 F1 Longtail - sits above the 650S coupé and Spider in McLaren’s range of so-called ‘Super’ models. The P1 is in the ‘Ultimate’ range and the recently-unveiled 570S and 540C sit in the newly-created Sports Series.

The 675LT features a more powerful and significantly modified 666bhp version of the 650S’s twin-turbo 3.8-litre V8.

McLaren says 50% of the parts in the V8 engine are new, including new turbos, new camshafts and connecting rods, a faster-flowing fuel pump and delivery system, and detail changes to the cylinder heads and exhaust manifolds.

So extensive are the engine changes that the unit has a new codename: M838TL. Power rises 25bhp over the 650S to 666bhp, with peak power arriving at 7100rpm. Torque is up from 500lb ft in the 650S, to 516lb ft at 5500-6500rpm in the 675LT.

As with the 650S, the engine is mated to a seven-speed dual-clutch automatic gearbox, although it has had subtle changes to speed up shifts.

Extensive use of carbonfibre for the bodywork, and aerodynamic features and other lightweight elements in the engine, chassis and body, give the 675LT a dry weight of 1230kg, which is 100kg less than the 650S. As a result, the power-to-weight ratio is improved from the 650S’s 493bhp per tonne to 541bhp per tonne in the 675LT.

The combination of lighter weight and prodigious new engine outputs result in a 0-62mph time for the rear-drive 675LT of 2.9sec, some 0.1sec faster than the 650S. However, a greater improvement is had in the 0-124mph time, which is cut from 8.4sec to 7.9sec. The 675LT’s 205mph top speed is 2mph less than the 650S’s due to the extra drag of the aerodynamic set-up.

The 675LT’s look is significantly altered and reprofiled compared with the 650S. It features many aerodynamic features and an altogether more aggressive style. The Longtail Airbrake is a key part of the new design, being 50% larger than on the 650S.