Maleo creates milestone for Orbital Engine Corp

By Russell Williamson

WHEN Australia's Orbital Engine Corporation begins manufacturing its two-stroke engines for the Maleo car project next year, it will be the realization of more than 20 years of research and development.

Orbital Engine Corp was the brainchild of Perth inventor Ralph Sarich, who began with a dream to develop an engine which was more efficient, smaller and lighter but as powerful as conventional car engines.

However, a lot of changes have occurred since then and today's Orbital engines, and indeed the company's structure, would be unrecognizable to Sarich, who is no longer involved with the company on a daily basis.

But his original concept has remained with Orbital and the 1200cc, two-stroke three-cylinder engine meets all of the original aims in being lighter, smaller, more fuel efficient and less polluting than its competition.

Confirmation of Orbital's involvement in the Maleo project came when the minister for research and technology, B.J. Habibie, made the announcement in the Indonesian House of Representatives last month.

Habibie said the development of the four-door sedan was now ready to enter phase two, which would involve detailed engineering and testing.

The initial design of the vehicle -- which is expected to cost about Rp 25 million -- was undertaken by the Management Board for Strategic Industries in conjunction with Australia's Melbourne- based firm Millard Design.

Sixty prototypes are expected to be unveiled by the end of next year with full production beginning in 1998.

Production numbers will be ramped up to 100,000 cars per year over three years with the Maleo being sold both domestically and in export markets.

For Orbital, the selection of its engine to power the Maleo is a major milestone in the company's history because it will be its first volume production unit for the automotive industry.

Although the engine is already available in a Ford Festiva- based Orbital EcoSport in Australia, this was only a limited production of 100 cars.

These engines are built at the company's manufacturing facility at Tecumseh, Michigan, in the U.S. but the engines for Maleo will be built in Indonesia.

The engines for the Maleo will be very similar to those in the Orbital EcoSport and the Orbital S2s sports car, which was seen at the Jakarta Auto Expo in July.

The 1200cc three-cylinder engine produces a maximum power of 57kW at 4500rpm and a peak torque of 125Nm at 3500rpm.

However, it is in the areas of fuel consumption and emission levels where the real story behind this engine lies.

At the center of the engine's efficiency is the Orbital Combustion Process, which fires a mix of fuel and compressed air directly into the combustion chamber. The finely atomized fuel burns more efficiently by this method.

In testing by both Orbital and Porsche Engineering -- the latter racking up 600 hours in test labs, equivalent to 100,000km in normal use -- the engine has proven to be substantially cleaner and leaner.

When compared to a 1400cc four-stroke engine in a similar- sized car, Orbital claims its engine provides an improvement in fuel consumption of 25 percent with less than 6 liters/100km achievable.

On the emissions front, the Orbital engine is even more impressive and easily meets the ECE Stage III standards which are due to be introduced in Europe in 1999.

However, although the engine is frugal and clean, it is still a lot of fun to drive, which is evident in the Orbital EcoSport.

Delivery of the EcoSport's 56kW is peaky. It is also noisy, well above class average. However, it is a noise which can be exciting rather than annoying.

The engine's biggest advantage over conventional rivals is its welcome 25 percent torque increase, with useful amounts available low down.

Beyond the bald power and torque figures, this is an engine to be enjoyed.

Twist the ignition key and the engine rattles into life after a longer than usual cranking period. When cold, fast idle is a rattly cacophony, with 1500rpm registering on the tachometer.

This falls rapidly as idle stabilizes at around 700rpm. Rev to 2000rpm and it sounds a bit unrefined but as the revs climb, the sound is not unlike that of a Formula 1 car.

Between 3500rpm and 5500rpm in the lower gears, the engine's maximum power is produced eagerly, spearing the EcoSport through traffic with zest.

It is hard to resist the temptation to accelerate all the way to the 6200rpm red line in each gear, savoring the unrefined scream of the three pot, mounted low under the hood.

But the engine can also be driven sedately, almost like an automatic. Slot into fourth on the move and it pulls away cleanly from as low as 1000rpm. The engine repeats the trick in third from 750rpm.

When installed in the Maleo, this engine is likely to add a dash of ride finesse, and there are all the signs that a fabulous road car could emerge.