1. Overview
Private buyers’ favourite small car, the Mazda3 sedan or hatch, is now
available with a class-leading diesel engine that combines sporty driving with
impressive fuel economy.
Boasting a best-in-class 360 Newton metres of torque and 105 kilowatts, the
Mazda3’s hi-tech powerplant features a self-cleaning particulate filter trap and
Euro Step IV emissions.
The Mazda3 Diesel is expected to accelerate from 0-100kmh in 9.5 seconds and
comes standard with a six-speed manual gearbox. The transmission is shared with
the Mazda3 MPS, Mazda6 MPS and Mazda6 Diesel models.
Fuel economy is impressive with Government fuel tests showing that the Mazda3
Diesel can travel 916km on a tank of fuel at its combined average ADR 81/01 fuel
test consumption of 6.0L/100km and more than 1010km when on the highway
(5.4L/100km).
Priced from just $30,500 for the Mazda3 Diesel sedan or hatch, they are
available with the same generous equipment levels found in petrol-powered Maxx
Sport models but add Dynamic Stability Control and Traction Control as standard.
The Diesel’s safety package also includes dual front, front side and head
protecting airbags (six in total) and ABS anti-lock brakes with Electronic
Brakeforce Distribution and Emergency Brake Assist.
The Mazda3 Diesel shares its 300mm ventilated front (up 22mm on the 2.0-litre
petrol Mazda3’s front discs) and 280mm solid rear disc brakes (up 15mm on the
2.0-litre car’s rear discs) with 2.3-litre petrol Mazda3 SP23 variants.
Standard features include air-conditioning, power windows and mirrors, cruise
control, six-disc CD changer, wheel mounted audio and cruise controls, reach and
rake steering adjustment and an iPod compatible AUX jack.
Like the petrol Maxx Sport models, the new Mazda3 Diesel, which can be
identified by MZR-CD badges on both front doors, also features a body kit and
16x6.5 alloy wheels.
To translate the MZR-CD 2.0 turbo diesel’s high torque into controllable and
reliable traction, Mazda’s engineers stiffened the car’s chassis installing
special body shell reinforcements from the high-performance Mazda3 MPS – the
front suspension upper plate, front cowl member and middle tunnel cross member
have all been beefed up.
The driveshafts have also been upgraded to handle the additional 178Nm of
torque produced by the diesel engine over the Mazda3’s 2.0-litre powerplant
(that engine’s torque peaks at 182Nm).
Mazda3 Diesel’s MacPherson strut front suspension and multi-link rear
suspension feature unique calibration, and the front and rear stabilisers have
grown by 2mm to 23mm and 22mm respectively.
Taken together these chassis features provide superior road holding and even
more linear steering response from the car’s hydraulic power assist steering
system.
Managing director of Mazda Australia, Doug Dickson, said: “With the
introduction of the Mazda6 Diesel in October last year, Mazda became the first
and remains the only Japanese car maker to introduce a state-of-the-art diesel
engined passenger car.
“The sales success of the Mazda6 Diesel convinced us that a Mazda3 Diesel
would find a ready market here.
“Our own research confirmed this. Mazda’s target customers, the so called
high involvement buyers – Australians interested in the driving experience –
said they are attracted to diesel for the technology as well as the potential
fuel gains.
“And recent Roy Morgan data shows that 60 per cent of our target customers
would consider purchasing a diesel powered car in the next year. But only 47 per
cent of them would consider a hybrid.
“The Mazda brand and our vehicles have strong appeal with high involvement
buyers, therefore research such as the Roy Morgan data further validates our
decision to broaden the availability of this engine technology by offering it in
our most popular model, the Mazda3.
“We believe the Mazda3 Diesel with its class leading engine and great fuel
economy will deliver a superior Diesel driving experience to the Small car
segment. This fun-to-drive factor is after all what the Mazda brand and our
Stylish, Insightful and Spirited cars are ultimately all about.”
To the end of June Mazda had sold a record 17,776 Mazda3’s making it the
second best seller in Australia’s largest market segment (Small cars). And with
15,517 of those classified as private sales by VFACTS Mazda3 is the private
sales leader in this all-important market segment.
Mazda Australia expects to sell 130 Mazda3 Diesel models a month with the
sedan split likely to mirror the petrol variants, taking about 70 per cent of
the business.
The Mazda3 sales success has contributed to Mazda Australia’s best six
monthly sales performance with 39,112 retail sales in the first half of this
year.
The record half yearly result is 20.3 per cent up on the same time last year
and has lifted Mazda’s market share from 6.7 per cent in 2006 to 7.5 per cent, a
gain of 0.73 percentage points. No other car company has achieved such a large
market share gain.
Mazda continues to lead the importers outselling its closest full-line import
rival by 6936 sales (or a significant 21.6 per cent). Overall Mazda is fourth in
the market place, outselling one local manufacturer.
2. Diesel Technology
The Mazda3’s diesel engine is a Mazda designed and built MZR-CD 2.0-litre
common-rail turbo diesel engine that uses various technologies to ensure that it
comfortably meets Euro Stage IV emission standards.
Utilising a state-of-the-art ceramic filter system to capture particulate
matter, the Mazda3’s diesel engine virtually eliminates diesel smoke.
Once the filter has captured a pre-determined amount of particulate matter
exhaust gas temperatures are raised to burn it off and regenerate the filter.
Advanced common-rail fuel injection
The MZR-CD engine’s common-rail fuel injection system injects fuel at an
ultra-high pressure of 1,800 bar (180 MPa, 26,100 psi). The required fuel for
injection is accumulated under a pressure of up to 180 MPa in the common-rail.
Fuel injection volume, frequency and timing are optimised by electronic control
based on throttle opening and engine speed data.
Fuel atomisation is excellent, and fuel is injected in precise quantities in
immediate response to running conditions. This substantially improves the
engine’s combustion efficiency, to boost power and dramatically reduce NOx and
particulate emissions.
Relatively low combustion ratio
The MZR-CD’s low compression ratio (16.7 to 1) allows low-temperature pilot
premixed combustion, also reducing soot and NOx emissions.
Fuel is injected into each combustion chamber before the piston reaches top
dead centre, promoting combustion efficiency while minimising production of
particulate matter or black soot. In addition, the lower combustion temperature
helps to minimise NOx.
To enable optimal control of the air/fuel ratio, a high response intake
shutter valve and a valve to control the recirculation rate from the exhaust gas
recirculation (ERG) cooler are located on the intake side of the engine.
Residual oxygen in the exhaust gases is monitored by an O2 sensor and this
information is utilised by a 32-bit powertrain control module to optimise the
fuel/air ratio, continuously optimising the mix and suppressing NOx.
A catalysed diesel particulate filter reduces black smoke emissions to
virtually zero by capturing particulate matter in a ceramic filter. When a
specific quality of particulate matter is trapped it is automatically burnt off,
allowing the filter to return to its original efficiency.
The particulate filter enables the MZR-CD engine to cut its soot emissions to
80 per cent below the Euro Stage IV emission standard.
The relatively low compression ratio also reduces pumping loss and promotes
thermal efficiency. Typically a low compression ratio means inferior thermal
efficiency under low-load conditions, but this is offset by a combination of
high fuel injection pressure and the frequency and timing of the multi-stage
injections.
These attributes produce not only 360Nm of torque but combine with the tall
gear ratios provided by the Mazda3 Diesel’s six-speed manual gearbox to produce
impressive fuel economy numbers.
Variable Geometry Turbocharger
The engine also features a variable-geometry turbocharger that has a lower
inertia moment and features a short distance between the exhaust gas inlet and
the centre of the turbine shaft.
A variable-geometry turbocharger helps maximise torque over the widest range
of engine speeds. The Mazda3’s VGT is an update of earlier designs with the size
of the turbine reduced to lower the inertia moment by 14 per cent. In addition
the ratio between the cross sectional area of the narrowest part of the VGT’s
exhaust gas inlet and the distance from the centre of that area to the centre of
the turbine shaft has been reduced, producing smoother acceleration, a 10 per
cent power jump, a 10 per cent improvement in maximum torque and better fuel
economy.
The variable-geometry turbocharger is combined with the engine’s high
pressure common-rail fuel injection system, with optimised injection volume and
multi-stage injection of up to nine times per cycle, and a relatively low
compression ratio, all of which improve output and torque, repress combustion
noise and reduce emissions.
High torque, low NVH
The new turbocharged 2.0-litre MZR-CD engine has been developed to deliver
high torque while minimising noise, vibration and harshness (NVH).
Multi-stage injection, which is performed up to nine times per cycle,
prevents overly rapid pressure increase in the cylinders, suppressing diesel
knock and other combustion noise.
When the engine is idling the intake shutter valve restricts air intake
volume to reduce cylinder pressure by about 25 per cent and suppresses idle
knock, while the low compression ratio limits engine speed fluctuations and
significantly lowers vibration.
3. Mechanical Changes
Powertrain
- Sporty MZR-CD 2.0 common-rail turbo-diesel engine with maximum power of 105
kW at 3,500 rpm, maximum torque of 360 Nm at 2,000 rpm
- Euro Stage IV compliant with maintenance-free diesel particulate filter
system
- Low fuel consumption of just 6.0 litres per 100 km (combined)
- Six speed manual transmission based on high-performance flagship Mazda3 MPS
- Stronger drive shafts to match higher torque
- Diesel specific exhaust system
Chassis and Safety
- Front suspension upper plate, front cowl member and larger middle tunnel
cross member reinforcements from the high-performance Mazda3 MPS, for a stiffer
body shell
- Front and rear coil spring rates and dampers especially fine-tuned
- Larger stabilizers (+ 2 mm): 23 / 22 mm (front /rear)
- Larger brakes 300 mm / 280 mm (front / rear) with ABS, DSC, TCS, EBD and
emergency brake assist standard
Six speed manual shared with MPS models
The diesel engine mates to the same three-shaft gearbox used in the Mazda3
MPS and Mazda6 MPS models
To handle the engine’s high torque and to ensure smooth gear changing, first,
second and third gears feature triple cone synchronisers, fourth gear has a
double cone synchroniser and fifth and sixth gears have a single cone
synchroniser.
4. Pricing
Mazda3 Diesel sedan $30,500
Mazda3 Diesel hatch $30,500
* Prices correct at 14/8/2007
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