Go Gas! Falcon and Corolla aftermarket LPI models tested

[Jason[98.EL]]

http://ninemsn.carpoint.com.au/revie...s-tested-19625

Go Gas! Falcon and Corolla aftermarket LPI models tested

Models: Ford Falcon FG XR6; Toyota Corolla (Corolla prototype system under testing)
RRP: Falcon: Add $4400 fitted to donor model price (Corolla TBC)
Fuel: LPG/ULP
Claimed fuel economy (L/100km): est 14.9 LPG; 9.9 petrol combined cycle (Falcon FG 4.0 litre inline six)
CO2 emissions (g/km): 239 ULP/208 LPG (based on Orbital claims of reductions of up to 13 per cent against petrol)
Also consider: a number of systems available for a number of models from several aftermarket manufacturers



Later this year, Ford will overhaul its dedicated E-Gas Falcon with an upgrade to liquid injection. But Orbital Auto Gas Systems, the company supplying Ford with all components for the upcoming system forward of the tank, already makes the same technology available in aftermarket dual-fuel form on Commodore V6s and V8s and Falcon sixes.

This new generation of liquid injection LPG systems keeps the gas under pressure until the moment it is released into the intake manifold. Arriving through the jet as a liquid droplet rather than a vapour, it immediately expands 270 times into its natural gaseous state. The result is an improvement in combustion efficiency, producing modest benefits in fuel consumption and palpable improvements in power and torque outputs. This all but closes the traditional shortfalls that have long reduced LPGs attractiveness to consumers.

Dual-fuel LPG systems have advantages and disadvantages next to their petrol counterparts. On the good side, because dual-fuellers use bolt-on LPG systems rather than dedicated ones -- the original petrol system remains intact, making for a substantial improvement in range if you're prepared to use both systems. It's like carrying a couple of jerry cans around with you wherever you go.

It also used to be beneficial in providing petrol as a backup in the occasional moments of intransigence for which LPG systems were known. But with this generation, aftermarket providers like Orbital and Alternative Fuel Innovations say those old issues have been laid to rest.

These two outfits have been selected as component suppliers for Ford's upcoming liquid injection Falcon E-Gas: Alt Fuels providing the tank, Orbital the rest. Indeed as noted above, the Orbital-equipped FG Falcon Carsales tested uses the same components as the Ford's factory-fitted model will later this year.

Among the disadvantages of dual-fuellers is that the LPG systems have to use their own management module, operating outside the functional domain of the car's main engine management system (EMS). This means the engine remains optimised for petrol rather than LPG, and the gas system isn't integrated with ancillaries like the Falcon's instantaneous and average fuel-efficiency readouts. All the data coming from the car's original instruments pertains to the petrol system only.

This is where Ford's LPG-only E-Gas benefits most -- the whole thing runs off the one EMS, so the engine is mapped without compromise to accommodate LPG's different volumetric efficiency and combustion envelope.

For our seven day tests, Orbital also made available a Toyota Corolla hatch, currently still in testing. The company isn't sure when it will go to market.

At the wheel, the Orbital system is signified by a silver switch mounted on the fascia or console. About the size of a 20 cent piece, it has five LED bars around the top half of its circumference. When the tank is full, they're all lit in blue. As the tank empties, they go out one by one.

Ideally, when it's down to two bars it's time to refill. But should that elude you, it's handy that this generation of LPG systems solves one of the technology's old bugbears. Until not that long ago, the cutover from gas to petrol was manually switched, and it was a hard and fast rule with dual-fuels that you must not run the gas tank empty. To do so would result in a trip to the workshop with unpleasant financial repercussions.

This generation automates the cutover to petrol when there's still a small quantity of LPG left in the cylinder. The transition is seamless, marked by nothing more than a couple of beeps with the switch indicator flashing up the petrol symbol.

But for those beeps, the cutover is imperceptible in either car. In fact, it happens every time you use the car. It warms the engine up on petrol, then switches to LPG automatically within a few seconds of departure. Once you're off, you can switch manually between the two at any time, simply by pushing in the switch. A small bowser logo lights up on the switch to let you know when it's using petrol.

Orbital hasn't released the results of dynamometer testing for either the Ford or Corolla we tested. But testing on a V6 VE Commodore revealed slightly better power and torque figures over 91RON ULP. In our two test models, the smoothness of cutover and back-to-back runs through the same road loop on both fuels suggest it would take a very skilled driver indeed to detect any performance gap.

Dual-fuel systems necessarily need a second tank. In sedans like the Falcon, this sits behind the rear seats, consuming a sizeable chunk of bootspace. Fortunately, the Falcon has an enormous boot.

Being a small hatch, the Corolla requires a little more ingenuity. It's not possible to simply bung the tank in the boot -- there's too little existing space with the rear seats up and it ruins any use one might make of folding them down. So they're running this prototype with a 38 litre toroidal (donut-shaped) tank in the wheel well under the boot floor, replacing the spare with a tyre repair and inflator kit.

If the Corolla is to go to market there's every likelihood the hole in the donut will be filled, adding another four litres' LPG capacity.

So, is it worth the money? Dual-fuel systems don't have the elegance of fully integrated, dedicated systems but this generation will present no operation problems for the average urban driver. And if you're putting in 20,000 km a year it's likely to save you well over $1000 a year in fuel.

Whether it's worth the $4400 spend on the Falcon depends on your driving patterns, what you expect of the car and how long you plan to keep it (The Corolla system has yet to be priced, but it's safe to say it will come in a little cheaper than the Falcon's).

While liquid injection delivers a slight improvement in fuel efficiency over the vapour injection systems they supersede, the traditional LPG value proposition remains intact: a 30 per cent disadvantage in fuel consumption mitigated by a 50 per cent-plus advantage in fuel price.

Where these latest systems come into their own is on the performance side, closing gap between the LPG and petrol systems. What you get now is a car that performs as well on either side of the switch.

Interesting that they are putting the falcon against the Corolla

Jason