HCCI (Homogenous Charge Compression ignition)

HCCI: is this the future ?
Could the be theway forward for the petrol engine?
GM thinks so and could introduce it within three years
GM IS PREDICTING diesel-like economy and CO2 emissions far its next generation of petrol engines.

The company is hard at work on new technology called HCCI (Homogenous Charge Compression ignition). Essentially it combines existing direct election and variable valve timing technologies with cylinder pressure sensors. Fuel is burnt at lower temperatures and so with the great efficiency - with up to 15 Per cent better economy. It also means cheaper engines as the fuel burns at low enough temperatures 21 amid the production of NOx gases - which currently need to be reduced with pricey 'after treatment' systems.

"Despite its complexity, compared to a diesel there are great cost benefits to the HCCI system," said Dr. Uwe Grebe, GM's director of advanced engineering. "With all of its benefits, it could be a better solution for many buyers."

There's no word yet on when HCCI will come to market, but with prototypes already in advanced stages of testing it should be on production cars by the end of the decade.

GM plans more conventional fuel -saving solutions next year. The 170bhp 2.0-litre turbo, powering the Opel Astra and other models, is being replaced by a 1.6-litre turbo. Power has been boosted to 180bhp and early predictions are that economy and CO2 output are improved by an impressive 14 per cent.

There's also new diesel tech in the offing. By the middle of next year the Saab 9-3 and Cadillac BLS will have a new 1.9-litre four-cylinder turbo option. A two-stage turbo gives it 180bhp and 40.7kgm.