One-off new Lamborghini Aventador J roadster revealed

Despite appearances, this is not the new Lamborghini Aventador convertible. It is actually something a lot more special: the Lamborghini Aventador J, a one-off roadster that does without a roof or windscreen to make it one of the most extreme Lamborghinis ever. Let's hope the eventual proprietor owns a garage.

That J moniker might sound strange, but it is a nod to the one-off 1970 Miura Jota and the FIA's Appendix J racing regulations to which Lamborghini's racing cars must conform.

After its outing at the Geneva Motor Show, this J, the only one in existence will go to its owner who will take possession of one of the world's rarest cars. No prototypes, no museum versions have been built. What you see here is the only J in existence.

What's new about the Lamborghini Aventador J?
Its privileged owner is in for a treat. Lamborghini compares the J experience to that of riding a superbike. Wet weather gear and a helmet is what Lamborghini reckons you need to fully exploit the J. It is completely roofless and the windscreen is a mere slip of wind deflector, like a KTM X-Bow or the special-edition Mercedes-McLaren SLR Stirling Moss.

Power comes from the same 6.5-litre V12 that powers the Aventdaor coupe, combining 700hp , a semi-automatic gearbox and permanent all-wheel drive for true any-weather performance.

That means, together with the improvements in weight, it should better the regular car's 0-62mph in 2.9 seconds and top speed of 217mph.

What's it like inside?
Lamborghini has reengineered the monocoque to fit two new safety bars behind the front seats. Everything unnecessary has been stripped out to make this an extreme experience, including air-con and sat-nav. The seats are constructed of carbonfibre and a new high-tense composite combound has been developed by Lamborghini for the J. The cockpit has also been shrouded in carbonfibre, so expect this to filter through to future models.

What about the rear-view mirror?
One of the Aventador J's most striking features is the periscope style rear-view mirror. Perched on arms, it gives the J a concept-car like presence and contrasts with the rear spoiler, which is also propped up on arms.

What else has changed?
The J is longer and lower than before to accentuate its profile, with a narrower front end to aid driveability, while it wears new alloys, 20-inches at the front and 21 at the rear for a pointy, aggressive stance.

At the rear, the J gains a huge spoiler, a carbonfibre rear diffuser and four exhausts pipes and carbonfibre fins have been added to the front and rear bumpers to increase downforce at speed.

How much will it cost and when is it on sale?
It's anyone's guess how much this one-off Lamborghini will cost its future owner, and we'd imagine a buyer has snapped it up already. What's more exciting, though, is that the J gives us a clear indication that a) Lamborghini will make a convertible Aventador, and B) that far from going soft, Lamborghini is back to making more extreme cars than ever.

We won't hold our breath for a drive of this exclusive model...

Read a Lamborghini review
On Bing: more pics of the Lamborghini Aventador convertible
Revealed: Ferrari F12 berlinetta