27 September 2012
It’s a gas
The Holden Commodore, with its large capacity engine options has never been considered a fuel miser. But over the past few years the pursuit of fuel savings and lower greenhouse gases, as with all car manufacturers, have been priorities for Holden and plenty of improvements have been made to their engines and the way their mapping is programmed, to optimise the combustion process.
A few technology savvy systems were introduced in an effort to bring down running costs without significantly jeopardising performance.
Holden introduced Active Fuel Management (AFM) for their V8’s to switch off four cylinders when full engine performance isn’t required, and Spark Ignition Direct Injection (SIDI) used on the V6 motors accurately injects petrol straight into the combustion chamber for increased engine efficiency. They’ve also been active on the bio-fuel front, with Flex-Fuel cars which can run on up to 85% ethanol and 15% gasoline-mix.
Holden is no stranger to using Liquefied Petroleum Gas (LPG) in their vehicles either, and have been installing gas systems for almost twenty years. The latest entry to the range is the dedicated LPG Commodore. Five body choices are offered with the LPG powerplants; the Omega, Berlina and SV6 sedan as well as the Omega and SV6 wagons.
The cleaner choice
At first glance, the SV6 sedan looks like any other petrol-guzzling Commodore. The only visual hints that this vehicle is LPG powered is a discreet badge on the rear boot lid and a label on the front bumper to comply with local legislation.
Holden have developed a unique vapour injection process and consider their injection system superior to the liquid injection method normally used by car manufacturers. A purpose-built element heats the fuel, causing it to vaporise, ready for spraying into the combustion chamber. They say this method better reduces CO2 emissions and gas consumption.
The 3.6L V6 petrol engine is fitted with new pistons, hardened valves and hardened valve seats to accommodate LPG, which is a drier, more abrasive fuel. The compression ratio is raised to take full advantage of the higher octane and thus increases performance.
The 3.6 litre V6 engine is the only powerplant available with the dedicated LPG system, and power output of 180kW/320Nm is only 30kW/30Nm shy of the gasoline-only SV6 which produces 210kW/350Nm. The motor is mated to a lighter, more refined, six-speed automatic transmission and fuel consumption is claimed to be 12.3L/100km, with exhaust emissions of only 198g/km CO2; pretty impressive for a large engine.
The LPG gas tank is fitted behind the rear axle for a good balance of weight distribution. This is out of sight and removes the need for an intrusive cylinder in the boot. It’s constructed using high strength, multi-celled, aircraft grade extruded aluminium with strategically placed protection plates. Holden conduct stringent physical tests on the gas tank as well as crash tests with the tank fitted to the vehicle to ensure high safety levels.
The biggest obstacle facing alternative fuel car manufacturers is the range-anxiety normally associated with these vehicles. Holden overcome this by installing a large eighty-four litre, lightweight, aluminium gas tank in an effort to change driver perception, allowing the car to travel around 700km on a full-tank. Gassing up should not prove too difficult, either, with around 570 LPG car-friendly gas stations around NZ, although it might pay to take note of their location when planning a long trip.
The floor of the boot is slightly raised compared to the petrol version but it still manages a useful 481 litres of storage space. The spare wheel is eliminated and substituted with a tyre sealant compressor kit, although an optional space saver-spare wheel is available.
The SV6 suspension is treated to stiffer springs and dampers for a sportier ride. Eighteen-inch alloys wheel rims are standard.
Active safety features include Electronic Stability Control (ESC), Electronic Brake-force Distribution (EBD) and Traction Control System (TCS). Passive safety comes with six airbags and the car achieves a 5-star ANCAP safety test rating.
Creature comfort features are dual-zone climate control air-conditioning, leather wrapped multifunction-steering wheel and auto headlights. Optional features are a reversing camera and a touch screen satellite navigation system.
The LPG Commodore may seem to consume more fuel than the petrol model but it is a significantly cheaper fuel and puts fewer pollutants into the atmosphere. Although large cars are generally being confined to the history books, for those fleet operators still needing something big, LPG could be something worth considering.
The SV6 LPG sedan has a sticker price of $58,990.