The new three-cylinder engine will be a variation on Volvo's 2.0-litre four-cylinder turbocharged and supercharged petrol drivetrain offered in the brand’s cars today, but without a supercharger, and with a 1.5-litre displacement.
The lack of a supercharger, according to Volvo director complete powertrain engineering Lutz Stiegler, is because the petrol engine only really needs that tech for instant torque in the higher-output four-cylinder drivetrains – the “six-cylinder replacement” engines, as he put it this week at the launch of the 2018 Volvo XC60 in Spain.
Stiegler said the three-cylinder drivetrain will be advantageous for both the company and the consumer: it will offer a lower-emission option for the company to lower its fleet emissions, and will give fleet buyers – in Europe in particular – an eco-focused engine in some of the brand’s most popular models.
“More specific to this car [the XC60], it’s not in yet,” Stiegler said of the chance of a three-cylinder XC60. “In an entry-level V60 or S60, it could make sense.”
Other models that will be a walk-up start for the three-cylinder include the all-new 40 series range, with the 2018 XC40 compact SUV to get the three-pot as a mainstay of the range, and the next-gen V40 and possible S40 compact sedan expected to get the tech, too.
“The 40 series will definitely get it. That car – the XC40 – is significantly smaller. That is the main reason to make the variant, to achieve very low CO2.
“When this engine is introduced, in the models that will have it we will not offer the same variants with four-cylinder engines. It is, then, a natural variant in the engine line-up as part of the powertrain family,” Stiegler said, indicating that the existing T3 and T4 petrol variants could well be powered by three-cylinder engines in the future.
The company has previously stated that the power output for this engine is expected to be pegged at 134kW, and a torque figure of at least 200Nm is predicted. But as with many other small-output turbo engines, there will likely be a couple of different power variations for different applications. Ergo, a T3 with a lower output than a T4.
And, for Europe at least, there’ll be a six-speed manual in addition to an eight-speed automatic.
“There is a chance of a manual, yes,” Stiegler said, agreeing that a six-speed would make sense for a stick shift, alongside an eight-speed auto.
“I think the amount of the speeds/gears – I don’t see a link between the number of cylinders and the number of gear speeds. More the other way around, I would imagine: the smaller the engine, the more the gears,” he said.
Along with the potential for a couple of three-cylinder purely petrol versions, that engine will also form the basis for a new type of plug-in hybrid drivetrain, Stiegler said.
“As it was announced last year at the event in Gothenburg in 2016 with the 40.1 and 40.2 concept cars, I think the drivetrain was also shown there, and it was a three-cylinder drivetrain with a plug-in,” he said.
“It’s not the same plug-in we have in the T8: it’s only one motor in the front,” he said, indicating that those PHEV models would be front-driven. “It will not have electric all-wheel-drive, as we have in the T8, which has a system that means that when it’s hybrid, it’s always in all-wheel-drive.”