Lotus has revised its Elise and Exige sports cars for 2009 - but you won't see the difference because the changes are all under the skin.

You will notice them at the pumps, though, because the maker is claiming up to nine percent less fuel consumption through weight reduction and engine efficiency.

Top performer, it says, is the Elise S, which has reduced its thirst from an average 8.3 litres/100 to 7.6.

Lotus CEO Mike Kimberley put it thus: "The Lotus philosophy of performance through light weight is even more relevant in today's emission-focused ecological world. It enables us to offer superb performance in some of greenest sports cars on the market."

He compared the Elise SC against other models of similar performance, using their manufacturers' own figures:

Lotus Elise SC

0-100km/h: 4.6sec

Fuel consumption: 8.5 litres/100km

CO2 Emissions: 199g/km

Price: R599 000

Porsche Boxster S

0-100km/h: 5.3sec

Fuel consumption: 9.5 litres/100km

CO2 Emissions: 223g/km

Price: R695 000

Mercedes Benz SLK 55 AMG

0-100km/h: 4.9sec

Fuel consumption: 12.0 litres/100km

CO2 Emissions: 288g/km

Price: R844 000

Ferrari F430 Spider

0-100km/h: 4.1sec

Fuel consumption: 15.2 litres/100km

CO2 Emissions: 345g/km

Price: R2.6-million

2009 LOTUS RANGE

Elise S: R450 000

Elise R: R520 000

Elise SC: R599 000

Exige S: R660 000