The petrol engine that could kill diesels

Variable-compression engine to feature first in Infiniti QX50 SUV

Infiniti unveils ‘most advanced internal combustion engine ever’

THE Renault-nissan Alliance is to launch the world’s first variable-compression engine in a production car, amid claims it will greatly reduce reliance on diesel power.

The groundbreaking 2.0-litre turbo VC-T petrol is said to offer the performance and refinement of a V6 but with much improved efficiency, and is being hailed as the “most advanced internal-combustion engine ever”. It will debut at October’s Paris Motor Show.

Infiniti will be the first Alliance brand to feature the new four-cylinder engine; it will eventually replace the ageing 3.5-litre V6 petrol used across Infiniti’s line-up. The first model to benefit will be the new QX50 SUV, due in 2018 and hinted at by the QX Sport Inspiration concept at April’s Beijing show.

Eventually, the VC-T is likely to find its way into models made by sister firms Renault and Nissan, and Infiniti could even choose to license the tech to other car makers.

It works by altering the volume of the combustion chamber between the top and bottom piston position. This gives different compression ratios, ranging from 8:1 to 14:1.

A low compression ratio delivers superior performance; a higher ratio allows improved fuel economy. The volume is changed via a new multi-link mechanism and control arm, and the engine automatically applies the optimum ratio for the driving conditions.

Infiniti claims a maximum 200kw output for the VC-T, which equates to approximately 270bhp, and 390Nm. It’s said to be around 27 per cent more efficient than the 3.5-litre V6, and 10 per cent up on comparable 2.0litre petrol rivals. Consumption is on par with 2.0-litre diesels, while performance is said to be 10 per cent up on 2.0 turbo petrol rivals.

A spokesman said: “This won’t replace all our diesels. But it has that potential.” It’s lighter than the latest diesels, plus cheaper to make. Pairing the VC-T with a CVT box is said to maximise efficiency, and Infiniti says the transversely mounted engine, developed entirely in house, could be used in hybrids. Eco and Sports modes will be offered, too.

Infiniti started work on the technology in 1998, and president Roland Krueger said: “This is the result of 20 years of research for Infiniti and is the next step towards meeting emissions regulations.”

“This is the result of 20 years’ research for Infiniti and is the next step towards meeting emissions regulations” ROLAND KRUEGER President, Infiniti