Toyota targets conventional engine in defense of green image

In the race to boost fuel economy, overhauling the internal combustion engine is all the rage. Ford, Hyundai and Mazda are among those focusing on direct injection, turbochargers and improved transmissions as they reinvent their powertrain lineups.

So with its emphasis on hybrids, Toyota Motor Corp. may be missing the boat.

For all its r&d firepower, Toyota has been slow to popularize such technologies as direct injection and six-speed automatic transmissions. And it hasn't turned at all to turbochargers or dual-clutch transmissions, which rivals increasingly see as key ingredients in greening their fleets.

Now, with Toyota struggling to defend its image as an environmental leader, simply playing the hybrid card may not be enough. And in recognition of this, Toyota is aiming to bring direct injection, turbocharging and engine cylinder deactivation to a wider array of small cars.

"We know we can't rely solely on hybrid technology to meet all consumer needs in the future," Toyota Motor Sales U.S.A. President Jim Lentz said at last week's National Automobile Dealers Association convention.

Takeshi Uchiyamada, executive vice president for r&d, said that in the next five years, turbochargers and direct injection will go in more pedestrian models such as the Toyota Camry.

Other tweaks will include expanded use of start-stop technology, which saves fuel by turning off the engine when the car comes to a standstill, and advances in variable valve systems.

"From the outside, Toyota might seem somewhat behind," said Koei Saga, managing director in charge of drivetrain r&d at Toyota. "But though it's not widely publicized, we do have plans to improve those technologies."

Saga said fine-tuning Toyota's gasoline engines is key to maximizing mileage in its hybrids as well.

"When you think of fuel efficiency, the engine is the base for improvement," he said.

Saga noted that the Prius engine is among Toyota's most advanced.

It uses an electric water pump, a new exhaust gas recirculation system, which reduces emissions by pumping exhaust back into the engine intake, and an exhaust heat recirculation system to warm the engine during cold starts and improve efficiency.

Still, hybrids hold sway in Toyota's laboratories.

In his speech at the NADA convention, Lentz gave only cursory mention to refining the internal combustion engine. The focus was on hybrids, plug-in hybrids, electric cars and advanced batteries.

One reason for the emphasis is that Toyota has sunk a considerable amount of its war chest into hybrids. Eyeing annual hybrid sales of 1 million units as early as 2015, Toyota engineers say it is time to start reaping some of the cost reductions that come with mass scale.

Toyota aims to halve the cost of the hybrid powertrain in the next-generation Prius, Saga said.

It is little wonder Toyota executives enthuse about sexy technologies such as hybrids and advanced batteries, not such humdrum matters as variable valve lift. If you got it, flaunt it.

Toyota plans to bring out lithium ion batteries soon and is working on next-generation solid-state and metal-air batteries that could double lithium ion's performance.

But such advances, for all their promise, won't be here until 2030, Uchiyamada conceded.

Until then, Toyota will need to take a closer look at its basic engine strategy if it wants to fend off the pack of increasingly aggressive rivals trying to usurp its green car crown.

By Hans Greimel- Automotive News