DETROIT -- Fiat Chrysler Automobiles, playing catch-up in the U.S. fuel-economy race, will debut a family of advanced four-cylinder gasoline engines in the next five years.
The automaker will also introduce a plug-in hybrid minivan, offer more diesel engines and continue to replace six-speed automatics with eight- and nine-speed transmissions.
Among the five full-line automakers, including General Motors, Ford Motor Co., Toyota Motor Corp. and Nissan Motor Corp., Chrysler is last in fuel economy, according to the EPA's ranking of fleetwide fuel economy.
"We will meet our regulatory requirements," said Fiat Chrysler powertrain chief Bob Lee at the company's investor day last week.
The federal government will require corporate fleets to achieve a 54.5 mpg average by 2025.
The automaker will start showing significant fleet gains in next year's EPA tabulation when it receives credit for fuel-efficient vehicles already on sale, such as the Fiat 500e electric car, the diesel-powered Ram 1500, and the new Jeep Cherokee, which has a fuel-saving nine-speed transmission.
The new family of four-cylinder engines will replace the global automaker's sprawling portfolio of 40 different I-4s and their variations. The new engine family can be modified for different regions with bolt-on components.
Lee indicated that the new engine family will have high compression, direct fuel injection and turbocharging. It will use just two sizes of pistons and share common combustion chamber designs, he said. This will help Fiat Chrysler save money with economies of scale and in testing and certifying engines.
To reduce friction and pumping losses, engineers are developing camshafts and balance shafts that use roller bearings, variable water and oil pumps, and an offset crankshaft, in which the crankshaft is not directly below the pistons.
To cut weight, the blocks will be aluminum. The new engine family is code-named Hurricane and will replace the current I-4 lineup that was developed with Hyundai and Mitsubishi.
Last week Fiat Chrysler did not say when the new engine family will be in U.S. showrooms. But a good guess would be in 2016, with the arrival of the redesigned Dodge Dart.
In 2016, Fiat Chrysler will roll out hybrids, starting with a plug-in Chrysler Town & Country minivan. Lee said Chrysler also will offer mild hybrids, which use an electric motor to assist when the vehicle is accelerating, and vehicles with stop-start systems.
The company will also offer diesel engines in more vehicles.
Two fuels that likely won't expand in Fiat Chrysler vehicles are compressed natural gas and hydrogen, which is used in fuel cell vehicles.
Said Lee: "The technology is too expensive, and the infrastructure to create and distribute hydrogen with a net CO2 footprint reduction is not in place."
• Multiair valve controls to improve air intake, mileage and power
• Offset crankshaft to reduce friction
• Low-friction roller bearings on camshaft and balance shaft
• Lightweight aluminum block
• Variable-flow water pump for faster engine warm-ups
• Integrated head and exhaust manifold to reduce weight and improve turbo performance
• Direct fuel injection for high compression and power