Pebble Beach, California - Bugatti will produce 150 open-top versions of the Veyron super car at a starting price of around around 1.66 million euros (2.44 million dollars).

Similar to the coupe version, the Veyron Grand Sport is powered by a 16-cylinder 736 kW/1001 hp engine with a top speed listed at 407 km/h.

But the top speed of the convertible can only be achieved when the top is closed. Open air drives have a maximum top speed of 360 km/h, the car maker said.

Bugatti has modified the convertible slightly which has a rollover bar behind the front seats. The removable roof panel is made of polycarbonate and is transparent.

In the event of sudden downpours, the Grand Sport has a fabric top stored in the luggage space which provides temporary protection up to a speed of 140 km/h.

The first production version of the coupe was auctioned to the highest bidder on August 17 for 3.19 million dollars. Customers can buy the Veyron in European showrooms from March 2009 for around 1 million euros or 1.4 million dollars.

The Veyron is still the world's most expensive car, but Aston Martin is planning to unseat it with the One-77 - the code name for an unnamed super car. It will feature a hand-hammered aluminium bodywork with all details specified to the requirements of every individual owner.

The starting price is estimated at 1.56 million euros or 2.3 million dollars. (dpa)