BMW has now filled out its current (E93) 3 Series range with the addition of a convertible that incorporates the company’s first retractable hardtop.

It is claimed that the three-piece folding metal roof brings a number of advantages over fabric, including the opportunity to increase the area of glass for improved visibility while retaining enhanced structural strength.

Urban dwellers will also no doubt appreciate the added security benefits that a metal lid brings.

Visibility through the rear windows has been improved by an impressive 38% over the outgoing model.  The designers’ aim was to make the new car as coupé-like as possible and, from all angles, the bodywork below the shoulder line of the fourth-generation Convertible is similar to the recently launched 3 Series Coupé variant. 

The main drawback with a metal roof is heavier weight than cloth, but BMW says weight has been kept down through the use of thin-grade steel for the roof panels. The new model is described as a ‘true 4-seater’ and boasts bigger dimensions than its predecessor as well as a 55kg overall weight gain (the metal roof weighs in at 75kgs).

Prices may be around 10% up on the outgoing model, but BMW says that if the higher specification is taken into account the price premium falls to 2.9%.

Jim O’Donnell, managing director of BMW UK, said, “Our engineers and designers faced a significant challenge when replacing the outgoing, benchmark model.  We believe they have surpassed themselves.  The new convertible ticks all the boxes; cutting-edge design combined with innovative technologies, performance combined with refinement, impressive economy and low emissions.  It joins the 3 Series Saloon, Touring and Coupé models to offer customers the broadest choice and most complete range of cars in the Compact Executive segment.”

The E93 3 Series Convertible also incorporates advanced engine technology that BMW claims brings an overall 17% reduction in CO2 compared with the previous model as well as more power and performance.

For the first time in the BMW range, the entire line-up of petrol-engines in a particular model feature ‘high-precision direct injection’.  This ensures that all the fuel is efficiently mixed and burnt in the combustion chamber. 

The 320i SE Convertible becomes the entry point into BMW 3 Series Convertible ownership with an all-new 170hp four-cylinder Direct Injection engine. 

In the flagship 335i SE Convertible, high-precision direct injection combines with twin turbo technology to deliver 306hp at 5,800rpm (0-62mph in 5.8 seconds and 50-75mph is achieved in fourth gear in 5.9 seconds). The three-litre straight six in the 335i is the same engine as the 325i, but highly tuned. 

If the sensation of burning flesh when climbing into sun-exposed seats on a hot day is something of a bugbear, you’ll be pleased to know that BMW’s engineers have been working on something called ‘SunReflective technology’ on its optional leather upholstery. 

Embedded pigments in the leather reflect infra-red radiation in the sunlight in wavelengths of more than 720 Nanometers to reduce the temperature of the seats and arm rests by up to 20 degrees centigrade, BMW claims. It could mean fewer hot bots and fried thighs. 

Attention to detail in the design is also illustrated by a unique feature in the convertible market – a through-load function (luggage space tends to be at a premium where folding metal roofs are concerned).  With the rear seat backrest down, a 40 x 26cms aperture offers access to the boot, ideal for carrying a set of golf clubs.

All new Convertible models are equipped as standard with a six-speed manual gearbox.  However, with 60% of outgoing six-cylinder petrol-powered cars specified with an automatic transmission, the majority of new Convertible customers are expected to select BMW’s six-speed auto ‘box.

But what about that coupe-convertible market crossover issue that a metal roof brings? BMW maintains that traditionally, and somewhat surprisingly, customers who buy convertible cars rarely consider coupé models. Less than 7% of BMW’s Coupé buyers consider a Convertible as an alternative. The Coupé buyers are after more ‘hardcore’ sporting performance, BMW officials say. But conversely, Convertible owners expect to spend around GBP4,000 more on their car than the corresponding Coupé purchaser.

BMW believes that discrete customer groups justify retaining both a 3 Series Coupe and a Convertible range.

It is expected that two thirds of 3 Series Convertible customers will be male, over 80% married and most with at least one child and two or more cars per household.  With a relatively young average age of 43 years old and with a high average income of over GBP77,000, many will be company directors, own their businesses, or be successful managers.

In the UK (BMW’s second largest market, after the US, for convertibles) E93 Convertible sales are expected to reach 5,800 units this year. BMW GB is reporting strong advance orders for the new model range and says that over 40% of this year’s allocation is already accounted for.

Two model variants, the BMW 325i SE (GBP33,065) and 335i SE (GBP37,930) Convertible, go on sale in the UK on 24 March 2007.  These will be followed in April 2007 by the four-cylinder 320i SE Convertible (GBP30,630) and two more three-litre engined cars – the petrol-powered 330i SE Convertible (GBP36,395) and diesel-engined 330d SE Convertible (GBP36,770).

Dave Leggett