Smart is to fit a new stop-start system to all its petrol models as standard. The stop-start Smart ForTwo MHD was introduced in 2007, and as of October 2008 this technology will now be available on both the 61bhp and 71bhp petrol-engined models.The Smart ForTwo MHD stop-start system is claimed to reduce petrol consumption by eight per cent on the combined cycle, which means the new Smart ForTwo should return 65.7mpg on average, with CO2 emissions down by 9g/km to 103g/km. As the Smart ForTwo has an automatic gearbox, there is no clutch pedal to shut down and restart the engine, as in traditional stop-start systems. Instead Smart’s stop-start technology, termed ‘micro hybrid’ by the company, turns off the engine as soon as the driver brakes and slows the car to below 5mph. The car then starts again when the brake pedal is released.The Smart ForTwo CDI, which is expected to reach British shores early next year, has also received a new closed particulate filter that reduces diesel particulate emissions, but the car’s 88g/km CO2 output remain the same. Two new body colours and some interior alterations, including a new-look instrument cluster, are the only visible upgrades.