2007 Caterham Seven Roadsport 150 car

Caterham's legendary Seven family has been boosted with the arrival of the brand new 150 bhp Ford Sigma to deliver a rasping 270bhp per tonne for just £17,495.

The arrival of the 150bhp variant of the two seater marks a departure from Caterham's original plans when it first announced details of the replacement for the long serving K-Series engines last autumn (northern hemisphere).

The entry level 125bhp version of Ford's Sigma powerplant was so good when mated to the new, stiffer chassis, that engineers decided to raise the bar for the planned mid range model by a further 25bhp – not the 15bhp initially slated.

Prices for the 150 powerplant will start at £17,495 in Roadsport guise, or for those looking for a stripped down, more track focused model, the Superlight will weigh in at an attractive £20,495. The latter, with its carbon cycle wings, 6 speed box and uprated suspension, will offer a devilish 300 bhp per tonne and a 0-60mph time of around 4.6 seconds.

In order to reach the new output, Caterham engineers revised the intake, added butterfly throttles and recalibrated the engine mapping on the Ford 1.6 litre unit. The result is a throaty, torque filled unit delivering an extra 25 horses for just £1,500 more than the entry level Roadsport model.

The new mid range Ford Sigma Seven benefits from the same perfect blend of meaty torque, stiff lightweight construction, and exceptionally smooth power delivery that has made the 125bhp a winner with customers and the media alike.

More than 10,000 road, and 1,200 track, miles have been completed as part of the Sigma engine validation process making it the most rigorous R&D programme of its kind in Caterham's long and illustrious history.