Subaru has taken the diesel route with a brand new engine for the Legacy and Forester models, based on the Subaru Boxer engine design. The engine changes the opportunities for the Subaru range in Ireland, where following the VRT changes, diesel power is beginning to dominate. Michael Moroney reports on his Legacy test drive.

The new diesel powered Subaru Legacy is a car worth waiting for. The engine power and economy are impressive coupled with Subaru styling and value at €29,995 before delivery charges.

Subaru has at last entered the diesel market, combining new and economical power with a car range that has been well regarded for its all wheel-drive ability.

The Subaru has been starved of diesel power up to now, and it has been the single feature that has prevented many buyers taking the plunge towards the Japanese brand.

That's all about to change as the diesel engine shows its performance ability. I've had the Subaru Legacy saloon model on the road for a recent test drive and yes, I'm impressed.

Subaru has been linked with what is called a flat or Boxer style engine design for a number of years. Now the company has adapted this design to its new diesel engine, tapping as much power and a lot more torque from the diesel design than its equivalent petrol model.

To explain the engine difference over conventional engines as simply as possible it is necessary to understand that most engines use pistons that move in a vertical way, up and down to generate the engine power. With the Subaru Boxer engine, there are two pistons on each side of a horizontal engine, giving a compact power unit.

Subaru still packs in the engine capacity in cc terms into the new unit; it's marginally bigger than the 2.0 litre petrol model and has a longer stroke. Long stroke engines always give more torque and pulling power and that's certainly the case with the Boxer diesel engine.

The torque output is 70% greater and that's what converts into good acceleration and good pulling power. This high pulling power gives the Subaru Legacy a towing rating of 1.7 tonnes with a braked trailer and that's amongst the highest figure for a saloon car, up ahead of the Ford Mondeo, but still not as high as the Volkswagen Passat.

Subaru has a reputation for performance that too is not lost on the new Legacy diesel. The high torque engine delivers an acceleration performance that beats its equivalent petrol powered model. The 0 to 100km/hr rating is just 8.7 seconds, that's a second faster than the equivalent petrol powered Legacy. It's also much quicker than the competition including the BMW 318d.

And the Legacy achieves this with the addition of an all wheel-drive (AWD) system under the body. This extra drive system claims to give the car more stability in difficult road conditions. It will help on a greasy field surface and no doubt has towing benefits too while being no burden in terms of pace.

The car drives well with a good feeling of power when needed. The five speed gearbox is an obvious match for the new diesel engine. The gear ratios are higher to achieve comfortable driving. Initially I thought that a sixth gear would be a bonus but not so, this engine with its high torque can cope well with changing road conditions.

The AWD system does not add too much weight to the Legacy, which weighs in at 1460kg. That figure makes it lighter than some of the competition. This lighter weight is achieved by a number of features including the frameless side opening door windows.