Mercedes McLaren soft machine

The convertible SLR leads a group of high-performance newcomers set for the Frankfurt Motor Show in September.

Codenamed R199, the drop-top, carbon-fibre car has been seen testing in Europe ahead of its show preview on September 13 and sales from the end of the year.

And there is more to come, according to European sources. Mercedes is also planning a Frankfurt preview of the AMG flagship in its new C-Class range, an early look at its new compact four-wheel-drive and will release details of a gearbox designed to rival the double-shaft manu-matic that has been a success for Volkswagen.

There are also whispers of something new from Maybach. However, there is no official confirmation from Mercedes-Benz.

Development of the Mercedes-Benz SLR, designed by McLaren Cars and built at the McLaren Technology Centre in Britain alongside the team's grand prix race cars, has been picking up rapidly in the past year.

Sales of the original $1 million, 380km/h coupe were slow at first against rivals including the Ferrari Enzo and Porsche Carrera GT.

Then the car was tweaked into a limited-edition 722 model to celebrate the original SLR Stirling Moss drove to victory in the Mille Miglia road race in Italy in 1955.

The 722 code reflected his race number and starting time.

The droptop is planned to give the SLR a significant kick. European sources say it will be just as quick as the coupe.

The car is expected to have a folding soft-top because of limited storage space in the tail.

The C-Class star at Frankfurt will be the hotrod AMG model, with the latest 6.2-litre V8 engine already used in a number of cars, including the E63 and CL63.

The C63 AMG, coded W204, will need to be quick and refined.

It will have to go up against the V8 BMW M3, which is expected to be sold as a sedan as well as a coupe.

It will already be on sale when the blaster Benz arrives.

Mercedes will also use the Frankfurt show to uncover its compact 4WD, the MLK.

The X204 is the baby brother to the ML and will run up against several tough rivals, including the BMW X3. The MLK is expected to have an on-road focus, despite a traditional 4WD body, because it is being built up from the mechanical package used in the C-Class sedan.

The new gearbox for Frankfurt is the NAG-2V and will be a departure for Benz, which usually puts all its transmission work into automatics.

It is a sports transmission that uses a wet clutch to give the same combination of manual control with automatic convenience as VW's DSG gearbox.

It will be fitted to an SL63 AMG for the show.

The final newcomer for Frankfurt, still to be confirmed, is a development of the Maybach super-limo.

Mercedes has returned the stretched S-Class Pullman to its range and it is believed it will do a similar thing for Maybach, perhaps using a name such as Landaulet.