Holden Berlina LPG v Ford Falcon EcoLPI 2012 Comparison

Liquid petroleum gas (LPG) has long been the preferred choice of many fleet operators in Australia. With a price per litre typically less than half that of regular unleaded petrol, the savings comfortably justify the extra initial outlay for a factory-fit option, or an aftermarket conversion. And even moreso for private buyers, who get a $2000 rebate from the federal government for choosing to go LPG.

For local builders Holden and Ford, LPG is presented as something of a saviour because it takes a lot of sting out of large-car running costs. If an LPG version of a Commodore costs $2500 extra over the counter, the government rebate takes care of most of that, while the reduced fuel costs quickly disperse the rest. In XR6 form, the EcoLPI Ford is even better placed because the premium charged is exactly $2000 over the regular (auto) XR6.

These are the calculations Holden and Ford made much of at the launch of their respective dedicated LPG Commodore and Falcon models this year. Holden reckoned its new LPG-only Commodore will cost less to fuel up over 12 months than a Toyota Corolla, while Ford estimates the EcoLPI Falcon costs private owners less to run than its own Fiesta light car.

The appeal is obvious: Based on the combined average consumption figures quoted for current petrol and LPG versions of the Falcon, the fuel cost over 20,000 kilometres is dramatically less for the gas-driven models.

At a fuel pump price of 124.9 cents a litre (best quoted in Melbourne at the time of writing), a regular petrol Falcon six will consume something like $2470 worth of fuel over 20,000km. At 54.5 cents a litre for LPG, fuel cost for an EcoLPI over the same distance is around $1350.

BIG BERLINA BONUS
For this test, in the Holden corner, we sampled a Berlina LPG version. This made the comparison more complex because the gas car uses Holden’s larger 3.6-litre V6 as the base, where Berlina, in petrol form, is only available with Holden's smaller 3.0-litre V6.

Thus when quoting statistics we referred to models comparable to the Berlina that use the 3.6-litre petrol V6. The $2500 premium for a gas Berlina covers not just the cost of LPG, but also the upgrade to a larger engine.

Both carmakers have invested significantly in updating their respective LPG systems. Holden has gone from dual-fuel to dedicated vapour-injection LPG, picking up measurable benefits along the way. Ford has spent three years gearing up the Falcon to use liquid phase injection developed by Orbital Corporation Limited.

For an output of 198kW at 5000rpm and 409Nm at 3250rpm (petrol 195kW at 6000rpm and 391Nm at 3250rpm) the Ford system injects liquid propane into the inlet ports where it vaporises before entering the combustion chamber.

Fuel remains in a liquid state from the tank to the engine and requires priming before start-up. This is the main difference between the Falcon and Commodore systems: The former needs a few moments before firing up (no more than six seconds according to Ford), where the latter starts virtually instantaneously.

TECHNICAL BENEFITS
Whichever way you look at it, both systems advance the LPG cause. This is particularly the case with the EcoLPI Falcon, which manages not just to cut fuel consumption and reduce emissions compared to the previous LPG system, but has also upped both kilowatts and torque – making it the most powerful non-turbo Falcon six.

EcoLPI consumption is quoted at 12.3L/100km for the XR6 variant, while CO2 output is 199g/km. The petrol engine is quoted at 9.9L/100km and 236g/km.

The Holden, now optimised for LPG, does better than before, but its vapour injection system means the power figures of 180kW at 6000rpm and 320Nm at 2000rpm (the dual-fuel produced 175kW/318Nm) are still down on the 3.6-litre petrol equivalent (210kW at 6400rpm and 350Nm at 2900rpm).

The LPG Omega’s fuel consumption is higher than its petrol equivalent (9.5L/100km) at 11.8L/100km.

The compensation is that, also like the Ford, the Berlina emits much more attractive CO2 figures with an output of 189g/km compared with 228/km for petrol 3.6-litre V6 models (Consumption and CO2 figures vary throughout the Holden range, with the heavier models generally more thirsty and polluting).

Both Holden’s 3.6-litre V6 and Ford’s 4.0-litre inline six have undergone work to suit LPG. Both get higher compression ratios to benefit from LPG’s higher octane rating, the valve seats are harder because they work in 'drier' circumstances, and both have modified inlet systems.

Although Holden spruiks the advantages of vapour injection over liquid phase injection (it says fuel economy and emissions are better, as is start-up), Ford’s is undeniably the more sophisticated system. The Blue Oval's offering compensates for a minimally-longer start-up by virtually equalling economy and emissions, and jumping way ahead in terms of overall driveability.

Ford’s claim is that liquid propane injection means no rough running, no constant cranking and no loss of performance.

SPACE TO SPARE
We enlisted a Holden Berlina and Ford Falcon XR6 variants for this comparison – both autos. The course comprised a mixed route covering urban and highway conditions over two days and more than 500km. Consumption figures and accelerative ability, mainly with just the driver on board, were key considerations but so too was overall usability, practicality and driving behaviour.

An important assessment was load-carrying convenience – and here both scored better than their predecessors with the LPG tanks now located respectively out of sight and generally out of mind. But, although LPG Commodore and Falcon owners no longer to have to contend with a boot-gobbling gas cylinder, there remains one caveat applicable to both: The tank may now be under the floor, but the spare tyre isn’t, meaning the spare still needs to reside in the boot.

The test Commodore’s more compact deflated spare might have been less intrusive than the Falcon’s full-size wheel, but it still limited space.

Load-through was provided in both cases (a single, wide ski port in the Commodore and a more useful 60-40 split-fold backrest in the Falcon) but getting around the spare was a problem. As has been noted previously, an inflator kit (standard on LPG Commodores) is probably the better way to go.

For family use, it is also worth noting that both Commodore and Falcon have only one centrally located top-tether child’s seat mounting point.

ON THE ROAD
The Falcon's obviously deeper reserves of power were evident every time we hit the road. If the 4.0-litre engine is impressive enough in base petrol tune, it is moreso in EcoLPI form where it develops its maximum power at a significant 1000rpm less than the petrol version.

Apart from the slightly longer starting time (no special procedures required – just twist the key to initiate the fuel line priming), the Falcon responds to the accelerator with more willingness and, with a much higher final drive ratio, feels more relaxed on the open road.

The 3.6-litre Holden isn’t tardy either, helped along by its lower final drive ratio (than the Falcon) and is more than adequately responsive both from a standing start and in rolling acceleration at highway speeds. But the Ford always feels more muscular.

This would suggest – and it is borne out in the Falcon’s specifications – that it is the better car for towing a trailer, boat or caravan.

Our test also confirmed the manufacturer’s fuel economy claims: Over identical distances in identical circumstances our bowser-confirmed figures showed 12.0L/100km and 12.2L/100km for Commodore and Falcon respectively. Both trip computers read around 1.0L/100km higher.

Later top-ups, where each car was run in slightly different traffic conditions, tended to confirm the Holden’s official edge in overall economy.

The Falcon’s larger 88-litre tank would possibly yield a slightly longer cruise range than the Commodore’s 84-litre tank – although that is all a bit academic. Holden says the LPG Commodore has a potential petrol-equivalent cruising range of up to 700km. The Ford should be pretty much the same.

OUR VERDICT
Comparing LPG Commodore and Falcon is really a no-brainer if efficiency and driveability are the main criteria. The Ford is clearly the better-performing, yet is close to the Holden in economy and emissions figures. At the same time, similar accelerative performance differentials exist between regular petrol Falcons and Commodores anyway, so there is more at play here, in an overall sense, than just engine punch.

If you are the impatient type, the possibility of The Falcon's pause while waiting for the system to prime itself might be a slight inconvenience but, to be perfectly frank, this proved a virtually un-noticed deficit during our time with the cars.

Thus we'd give the Falcon the nod -- and both LPG cars the thumbs up as viable lower-cost options for family buyers. LPG's advantages are well harnessed by these latest iterations of the Commodore and Falcon.

Indeed, at higher levels of efficiency at prices less than half that of petrol, the pro-LPG argument has never been stronger.

And the good news? There is still a long way to go before LPG prices reach that dreaded tipping point where its use offers no running cost advantages.

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