Volvo has announced that it will build its cars exclusively around four-cylinder engines from now on.

The six-cylinder T6 and the five-cylinder T5, D5 and more recently the D4 and D3, are set to be killed off as the models they serve are replaced.

The move comes as part of a concerted effort by the company to lose weight from its cars at the same time as increasing efficiency. Four-cylinder turbocharged engines are much more efficient than five- and six-cylinder engines - as much as 25%, says Volvo - with greater performance potential.

It also means that Volvo can shrink and lighten their chassis, as part of a new "scalable platform architecture" that will see essentially the same chassis underpinning future 60, 70, 80 and 90 series cars.