By David Wilkins

Ford's C-Max has not just one, but two, new replacements. Five-seater and seven-seater versions of the out-going model introduced in 2002 shared the same body, but this time, the seven-seater gets its own longer body and a new badge, Grand C-Max.

Here, Ford is following the naming convention already established by Renault and Citroën to distinguish between long and short versions of the same people carrier, which may allow the company to save a few pounds on its communications budget, but Ford seems to have been pretty unstinting in its spending on the development of the cars themselves.

That's important because the C-Max and the Grand C-Max aren't just likely to be big-selling models in their own right; they also represent the first use of Ford's new C-segment (broadly speaking, Golf-class) platform which will soon underpin two million vehicles produced each year.

The most significant of these will be the next Ford Focus, which will be sold, with only minor variations, around the globe. Previous attempts by Ford, GM and others to produce so-called world cars haven't really worked out because different versions of the same model were so heavily "localised" that they ended up having very little in common with each other, a luxury Ford has decided it can no longer afford as it attempts to streamline its activities around the world under its "One Ford" philosophy.

And coming up with a new platform to replace today's Focus is a particularly demanding task; ever since the Focus was introduced in 1998 it has set a benchmark for chassis behaviour that the present second-generation version has maintained well into the later stages of its life.

Well anybody who is anxious about what the new C-Max and Grand C-Max have to say about the on-road performance of the next Focus can probably relax. The new cars have a round of improvements such as updates to the "control blade" rear suspension system, a wider rear track and a quicker ratio for the steering, which now has electric power assistance. That's an arrangement that saves energy but can lead to a loss of "feel", so Ford has been very careful to ensure that the best qualities of older hydraulic power assistance systems have been maintained. A new feature is the Torque Vectoring Control system, which can automatically brake the front wheels individually, mimicking the functioning of a torque vectoring differential that balances the power delivered to each front wheel in order to prevent unruly wheel-spin.

These measures all produce good results in the C-Max and Grand C-Max, but the really impressive element in the new cars' dynamic performance, and again this augurs well for the next Focus, is the introduction of Ford's EcoBoost engines to the C-segment. EcoBoost is a programme being followed by the company around the world to downsize its petrol engines in the interests of economy, while maintaining or even improving performance through measures such as turbo-charging.

For the C-Max and Grand C-Max, there is the option of a 150 horsepower1.6-litre EcoBoost paired with a manual transmission (previous EcoBoosts have only been available with automatics or Ford's dual clutch Powershift gearbox). This gives very strong performance for its size but it was the smooth and quiet manner in which it delivered its power in the C-Max I drove that really impressed; it displayed the low-end pull of a good diesel while preserving the smooth "top-end" and ability to rev of a decent petrol engine. Buyers in some other markets will be able to opt for an even more powerful (180 horsepower) version of the same engine but UK customers will have no real reason to feel short-changed. The 2.0TDCi diesel – this time paired with a Powershift transmission - I sampled in the Grand C-Max was also very good.

The new C-Max and Grand C-Max – which are pretty much the same car forward of the rear of the driver's doors - take their inspiration, in design terms, from Ford's iosis MAX concept car. Manufacturers are getting a lot better at injecting visual interest into fundamentally boxy people carrier shapes, and these cars are good examples of this. Ford's team under the leadership of the British (ex-Audi) designer Martin Smith has worked plenty of curves into the C-Max and Grand C-Max. In the case of the C-Max, the roof slopes down quite sportily towards the rear, while the roof-line of the longer Grand C-Max is maintained at a higher level in order to provide headroom for the occupants for the third row of seats.

Easy access to these, for children at least, is provided via a "central walk-through" aisle which is created by folding the narrow centre seat of the second row into the base of one of the adjacent chairs. Access to both rear rows is helped by a new feature for the Grand C-Max, which the standard C-Max does not enjoy; sliding rear side doors which will probably be a boon in tight parking spaces.

Both cars do share the same interior architecture, though. The design itself is a matter of taste but what is beyond doubt is the progress Ford is making in matching the sorts of materials and finish found in the interiors of cars from posher brands.

Ford has drastically cut the number of trim and engine variants available on the new cars and shortened the option lists by combining extras into about half a dozen combinations or packs, but the availability of separate C-Max and Grand C-Max models has probably increased the real amount of choice available to customers overall. One plus for customers is that all of the new cars are well equipped. Even the cheapest are Zetecs – that's a mid-level trim designation in the Ford system – rather than bare-bones entry-level models. And while such comparisons are always difficult, at least some variants are quite a bit cheaper than their predecessors.

The new C-Max and Grand C-Max represent a strong step forward and augur well for the next Focus.

Ford C-Max 1.6 EcoBoost 150 PS Titanium

On sale: October 2010

Price: £19,745 (C-Max prices start at £16,745 for 105 PS petrol version with Zetec trim)

Top speed: 127 mph

Acceleration: 0-100km/h (62mph) in 9.4 seconds

Fuel consumption: 42.8 mpg

CO2 emissions: 154g/km

Rivals: Peugeot 3008, Volkswagen Touran, Renault Scenic, Citroën C4 Picasso

Ford Grand C-Max 2.0 TDCi 140 PS Powershift Titanium

On sale: October 2010

Price: £23,245 (Grand C-Max prices start at £18,745 for 125 PS petrol version with Zetec trim)

Top speed: 123 mph

Acceleration: 0-100km/h (62mph) in 10.5 seconds

Fuel consumption: 48.7 mpg

CO2 emissions: 154g/km

Rivals: Renault Grand Scenic, Citroën C4 Grand Picasso, Peugeot 5008

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