First drive: Distillate diet makes Mazda3 meatier

JAPANESE car-makers have been slow to pick up the diesel baton, especially in the small-car segment, but that will change on September 1 when Mazda Australia launches a 2.0-litre common-rail turbo-diesel version of the Mazda3 - to be available here as either a four-door sedan or five-door hatchback.

First seen at the Geneva motor show in March, the Mazda3 Diesel will be priced just below $31,000 or about $3000 above the price of the similarly-specified Mazda3 Maxx Sport.

Mazda Australia anticipates selling only about 100 units a month, which is a similar volume to its larger sibling, the Mazda6 Diesel that was introduced in October last year – but about half the numbers being done by the Holden Astra CDTi diesel since its launch last year. Ford will launch its first diesel passenger model in the Focus next month.

Powered by the same Euro IV emissions-compliant 2.0-litre MZR-CD engine used in the diesel Six, the Mazda3 Diesel offers an identical 105kW of power at 3500rpm and 360Nm of torque at 2000rpm. This is about the same power as the 2.0-litre Mazda3 petrol engine, but double the torque.

In terms of fuel economy, it returns 6.0L/100km on the combined cycle, compared with 8.6L/100km for the petrol engine.

The Mazda3 Diesel enjoys a performance edge over the Astra manual, which delivers 110kW and 320Nm from its 1.9-litre twin-cam engine, and is well up on the 88kW/280Nm produced by the single-cam engine you get with an Astra auto.

Fitted only with a six-speed manual gearbox – the Mazda diesels are not yet engineered for an automatic transmission – the diesel Three accelerates to 100km/h in 9.9 seconds.

Mazda Australia managing director Doug Dickson said he was pushing to get an auto version, which he estimated would double the car’s sales potential, but there are no prospects for one in the foreseeable future.

“With diesel, we take the lead from Europe and they only want the manual, so at this stage there is no auto in the range,” said Mr Dickson.

“These are not huge volumes, but we are just putting our foot in the water with diesel.”

The Mazda3 Diesel has the same equipment as the petrol-engined Maxx Sport – including 16-inch wheels, spoilers, six airbags, ABS and foglights.

However, in line with Mazda Australia’s policy to make stability control standard on every newly launched model here, its also adds dynamic stability control as standard (DSC is a $1000 option on other Mazda3s, and the Maxx Sport’s price to $27,500).

With bigger driveshafts, a beefier gearbox with an extra gear (a six-speed as used in the turbocharged Mazda3 MPS) and extra body reinforcements, also from the MPS, the diesel is somewhat heavier than its petrol equivalent.

It also runs larger brakes from the sporty SP23, with 22mm-bigger ventilated discs at the front and 15mm-bigger solid discs at the rear.

Consequently, at 1410kg for the European model (which should be comparable with ours), the Mazda3 Diesel is some 190kg heavier than the petrol Maxx Sport variant.

DRIVE IMPRESSIONS:

EUROPEANS have been onto diesels for many years, mainly because diesel fuel over there costs about half what we pay in Australia, but the advent of common rail turbo-diesels has turned the diesel market on its head worldwide.

With huge bottom-end performance, low fuel consumption and greatly reduced emissions thanks to particulate filters and electronic controls, the old reputation of dirty and rattly ‘oilers’ has almost gone.

Japanese car-makers have naturally been slower adopters of the technology than the Europeans, but are increasingly turning their attentions to the European market and will therefore introduce more turbo-diesels in the future.

Mazda Australia was the first non-European car maker to introduce a small or medium-size diesel car variant here when it released the diesel Six last October – at least in the modern era.

Most people have forgotten that Mazda also had a brief foray with a sluggish 626 diesel variant in the mid-1980s, but that is probably best forgotten.

Now comes the Mazda3 Diesel, fitted with the same modern 2.0-litre turbo-diesel engine and six-speed gearbox used in the Six, which provides plenty of grunt as well as hybrid-like economy.

On an introductory drive around the hills outside Vienna in Austria last week, the Mazda3 Diesel seemed to have a less flat torque curve than what we are accustomed to with turbo-diesels these days.

The engine pulls strongly from 1800rpm, but drops away from about 2700rpm and definitely requires another gear by 4000rpm. It certainly felt lively enough, but wasn’t quite the grunty, lightweight rocket we expected compared with the diesel Six. Mazda says the Three’s quieter cabin could also play a role in giving the impression it’s slower than the distillate-dieting Six.

And the stats, confusing as they are, seem to confirm this impression. According to Mazda’s own figures, the diesel Three accelerates from rest to 100km/h in 9.9 seconds, yet the bigger (and 150kg-heavier) diesel Six does it in 9.5 seconds.

Mazda Australia says the former is a conservative factory figure, while the latter was the result of a real-world test conducted in Australia. It expects the diesel Three’s actual figure to be better than the official 9.9-second claim, and at least as quick as Mazda’s locally-produced 9.5-second 0-100km/h figure for the diesel Six.

Furthermore, the official fuel consumption figures are better for the heavier Six (5.9L/100km compared with 6.0L/100km for the Three), which is curious. Again, however, Mazda Oz says the diesel Three will be at least as frugal as the diesel Six in the real world.

Standing outside with the engine running, there is no doubt that a diesel is installed under the Three’s bonnet, but inside the cabin there is little engine noise at all. What does come through is a muffled rumble rather than a clatter.

High revs are certainly not an issue as the gearing sees the Mazda3 Diesel loping along at 110km/h with the engine turning over at only 1900rpm in sixth.

Road noise, however, seemed a little high so it will be interesting to assess this when we get the car onto familiar Australian roads.

Ride and handling were very good, with little indication of the extra weight located mostly over the front axle.

The car turned in positively and did not suffer from excessive understeer, while the ride was pleasantly accommodating and able to comfortably absorb the few bumps we encountered, which is not always the case these days.

The power-assisted electro-hydraulic steering had good feel and was well-weighted at speed, providing good directional stability on the motorway while being light and lively on the mountain roads and around town.

Inside the cabin, the diesel is unchanged from the regular model – in other words, it is a nice place to be, with sound styling and ergonomics, comfortable and supportive seats, a nice steering wheel and clear instrumentation.

Interestingly, the Mazda3 Diesel will not carry any badges identifying it as a diesel model – not that buyers these days have any reason to be ashamed of driving a diesel.

With better performance and economy, it is not just the environment that benefits.