Suzuki’s new A-segment entry, the Celerio, gets an additional engine option in April, when the K10C Dualjet engine is introduced in the city car. The powerplant, which incorporates Suzuki’s new Dualjet twin fuel injector technology, has the same peak output as its baseline sibling – the 68ps K10B – but enjoys increased torque and improved efficiency. The 1-liter, three-cylinder engine increases torque to 93Nm (from 90Nm in the K10B), and records carbon dioxide emissions of 84g/km when coupled with a 5-speed manual transmission. During a pre-launch interview with a number of Suzuki engineers, Engine + Powertrain Technology International was able to glean some insight into Suzuki’s intentions for the technology beyond its use in the Celerio.
Dualjet technology in the Suzuki K10C engine
Dualjet technology has already been implemented in the 1.2-liter engine found under the hood of the Suzuki Swift and, explains vehicle line executive Shigeki Suzuki, the OEM is already considering options for adding the technology to other engines in the Suzuki family, though the official company line is light on details. “We have plans to implement Dualjet into some other engines in the future. I’m sorry that I can’t say more, but we are having discussions. We already have it on the 1.2-liter engine, and the 1-liter engine is the smallest model, so maybe in the future we’ll move to larger capacities.”
The Dualjet engine features paired fuel injectors that were developed, Shigeki Suzuki explains, by in-house teams and representatives of Bosch – though other suppliers were involved in the project. “In general, core engine development was performed by Suzuki. Other key devices were developed together with a number of suppliers. Bosch was heavily involved in the key injector technology.”
The twin injectors, and their position close to the combustion chamber, ensure better fuel atomization, faster vaporization and a more efficient filling of the chamber. The engine’s higher compression ratio (12.0:1 compared with the K10B’s 11.0:1) increases the speed that flame passes through the fuel, and makes the burn more efficient. A number of countermeasures are employed to deal with abnormal combustion, including a revised piston crown design, cooling oil jets under the pistons, a new EGR system with integrated cooling technology, and an optimized water jacket for engine coolant.
Suzuki’s cooled EGR system
The technology is one that Suzuki feels has great potential beyond smaller models. Shigeki Suzuki also gave ETi an exclusive peek at a number of in-house video simulations that demonstrate how the twin injector technology improves the in-cylinder spray of fuel over standard injection. And given that the development team is already discussing further applications of the technology, it seems unlikely that Dualjet will remain limited to the Celerio (the new city car was actually the subject of a right-hand drive UK, Ireland, Australia and New Zealand recall a few days after the event, though this was due to a braking issue) and Swift for long.