Engines &
Transmission

 

As before, the Mazda2 range is powered exclusively by the 1.5-litre Skyactiv-G petrol engine and for the 2022 model year the 115ps version has been reintroduced alongside the 75ps and 90ps outputs.

Starting with the £16,475 75ps SE-L, the seven-model 2022 Mazda2 range is topped with the new £20,845 115ps GT Sport Tech model. The 90ps engine is offered in SE-L and Sport trims, with Sport cars offered with manual and automatic transmission. The popular 90ps engine is also offered in GT Sport trim and the 2022 model year sees this trim also offered with a choice of transmission for the first time. The flagship 115ps GT Sport Tech is exclusively matched to the six-speed manual transmission, and with the exception of the entry-level 75ps SE-L, all manual versions of the 2022 Mazda2 feature Mazda’s M Hybrid mild-hybrid system and now wear the e-Skyactiv G badge.

Across all models the 1.5-litre petrol engine has been refined to offer considerable efficiency improvements. The compression ratio has increased from 13.1 to 15.1 with the exhaust upgraded from a 4-1 to a 4-2-1 manifold. As a result Co2 emissions have dropped by 11 to 14g/km depending on output and transmission. As an example the popular 90ps Sport manual has dropped from 120g/km to 107g/km, while across the range the corresponding improvements in economy further enhance the Mazda2’s excellent cost of ownership credentials.

The 2022 Mazda2 also sees the introduction of Mazda’s unique, world-first Diagonal Vortex Combustion technology, in addition, the Skyactiv-G unit benefits from a new engine control programme created during the development of the e-Skyactiv-X engine, improving vehicle response to and control of acceleration.

In manual transmission versions of the 2022 Mazda2, improving the throttle’s response to accelerator operation and choosing gear settings that link together well have resulted in a responsive and rhythmical up-shifting of gears from the moment the car starts moving. Precise torque control also keeps vibration low when accelerating or changing gears, which in turn curbs driver and passenger head movement and allows occupants to enjoy smooth acceleration. For variants equipped with an automatic gearbox, the transmission time and timing has been fine-tuned so that occupants can use their innate balance ability in response to gear changes. The acceleration inclination before and after gear changes has been made more uniform, smoothing out acceleration and minimising occupant head and body movement.

The balance between transmission time and timing has also been carefully adjusted so that occupants can keep their heads stable with minimal body movement.

Other technical features include precise fabrication of the air intake port and optimised piston configuration. Precise crafting of the air intake port configuration increases intake-generated vertical vortex tumble. Geometry optimisation by reducing the height of the piston head bowl intensifies tumble during the compression process and increases turbulent energy at ignition. These measures result in fast flame spread after ignition, and prompt completion of combustion without generating abnormal combustion. This translates into improved low- to mid-range torque and better fuel economy at high speed.

Furthermore, high fuel injection pressure of 30 MPa and a multi-hole injector enable faster atomization over a wider area and achieve efficient, less wasteful combustion that steadily vaporizes fuel before it can adhere to the cylinder walls. Furthermore, during the cooling period, which is prone to the generation of particulate matter, the use of three-stage split fuel injection improves vaporisation and atomisation and reduces the generation of particulate matter during combustion by about 80%.

Improvements to the coolant system have also improved efficiency with a coolant control valve system almost completely stops coolant flow around the combustion chamber during initial warm-up to prevent heat loss. Vaporising petrol when cold requires the extra injection of fuel. But the coolant control valve quickly raises the chamber wall temperature, reducing that excess fuel volume to about half that of the previous Skyactiv-G 1.5 model, thereby improving fuel efficiency.

The 2022 Mazda2 version of the 1.5-litre Skyactiv-G engine also features an oil ring with an asymmetrical profile with a larger radius on the upper circumference and a smaller radius on the lower circumference. This optimises oil film thickness during vertical piston action, reducing mechanical resistance. The ideal, barrel-shaped curvature of the piston skirt further reduces mechanical resistance, which in turn improves fuel economy

Working in conjunction with the Mazda M Hybrid system, all versions of the Mazda2 are equipped with the i-stop idle-stop technology as standard. Developed entirely in-house and tailored specifically for its application in Mazda’s Skyactiv engines, the i-stop idle-stop system uses combustion energy for restarting the engine, and only requires an electric-powered starter motor to provide a small degree of momentum during the initial restart phase.

The lightweight Skyactiv six-speed manual transmission –delivers the same effortless, crisp and precise wrist-flick gear changes, as those enjoyed by MX-5 drivers. The key element to achieving this quick and decisive gearshift action is a larger gear lever ratio, but this in turn effectively reduces the internal stroke. To counter this, Mazda’s transmission engineers developed a small module spine that allows for exceptionally precise synchroniser and torque transmissions even with the desired 45mm short gear lever stroke. Shift effort gradually falls away during the gearshift action, resulting in a reassuring resistance during the initial movement of the gear lever, followed by a lighter touch to create the tangible feeling of the gears meshing cleanly in to place.

Combining competition-beating torque capacity with lower internal drag, the six-speed transmissions require 45 per cent less transmission oil than previous generations. The Skyactiv-Drive six-speed lock-up automatic transmission used in the Mazda2 is smaller and lighter than the Skyactiv-Drive variant used in the Mazda3, Mazda6, Mazda CX-30 and Mazda CX-5. As in these models, the key requirements were strong fuel economy, a direct and engaging feel, smooth and quick shifts and prompt responses.