THE ENGINES IN THE NEW VOLVO V70 - ECONOMY, POWER AND PERFORMANCE

The high-performance version of the Volvo V70 has the designation T5. Under the bonnet, there is a five-cylinder, 2.3-litre turbo that develops 247 hp and a torque of 210 lb.ft.

Initially, the Volvo V70 will be manufactured with a choice of three five-cylinder engines. In addition to the T5, there will be a 2.4-litre light-pressure turbo with

More engines on the way
Soon, five-cylinder normally-aspirated engines will also be added to the range. These will also be characterised by fine response, low fuel consumption and low emissions. One of them, 170 bhp, will meet the American ULEV (Ultra Low Emission Vehicle) requirements. Both the 170-bhp and the 140-bhp unit meet the European emission requirements for the year 2005.

Volvo Car Corporation is currently in a phase of intensive upgrading of all its engines. The upgrades, to RN (Revised N) status will take place successively and are already complete for all normally-aspirated engines and the 2.4-litre light-pressure turbo. Other turbo engines will follow in the near future.

Livelier, quieter and more fuel-efficient
The upgrades – which are so extensive that basically all moving parts are new – mean that the RN engines have a number of clear advantages over the earlier N generation:

Here are some examples of the most important technological solutions that contribute to the benefits of the RN engines:

Variable valve timing
CVVT technology (Continuous Variable Valve Timing) means greater low-speed torque and lower fuel consumption. This has already been introduced on all engines.

The technology means that the camshafts can be turned by up to 20 degrees (the inlet cam on the aspiration engines and the outlet on the turbo). This makes it possible to vary the timing between the inlet and outlet phases.

With this system, it is possible to close the inlet valves earlier in relation to the opening of the outlet valves, which generates higher torque at lower engine speeds.

When driving on the open road, when the engine is not running at full capacity, maximum overlap is used — i.e. the exhaust valves do not close until the inlet valves are already open. This means that some of the exhaust fumes are drawn back into the cylinder at the same time as the new fuel-air mixture is injected. Since some of the mixture is replaced by exhausts, the engine becomes more fuel efficient. This is an excellent method when full power is not required. Nothing is however noticeable to the driver.

Less mass, less internal friction
By making many of the vital moving parts – pistons, gudgeon pins and counterweights, for example – smaller or lighter, the movement mass in the engine can be reduced by about 25 per cent. This means that the engine has to move 3.5 - 4.5 kg less, depending on variant.

Since the piston is shorter, the connecting rod can be longer. This in turn gives a smaller vertical angle and means that the lateral forces — and thus the friction — are reduced as the piston moves.

Less mass in movement and less internal friction offer many advantages. Performance is improved while noise level and fuel consumption are reduced.

At the introduction of the new Volvo V70, it is only the 2.4-litre light-pressure turbo that uses these smaller and lighter moving parts. The other turbo engines will be upgraded successively.

New gearbox
The Volvo V70 is to be introduced with a five-speed automatic transmission, specially developed for the five-cylinder engine. The gearbox is adaptive, i.e. it automatically adapts the shift points to the driver’s style. A manual winter mode gives better starting capability and handling on slippery roads.

Geartronic is an automatic transmission that also allows the driver to shift manually. It is available on all petrol-driven turbo variants of the Volvo V70. The manual alternative is the well tried and tested five-speed M56.