Test drive Honda Civic i-DTEC: a samurai with a diesel heart

Testing the new edition of the bestseller with an impressive 1,6-liter diesel

The tenth generation Civic is significantly different from its predecessors. The model has become much larger, approaching the size of the middle class. The body looks more dynamic not only due to the greater width and length combined with a lower height, but also thanks to the bright expressive means in the design. Even in its most standard version, the Civic resembles a well-equipped racing car while being based on a new platform with much more strength, torsion and folding resistance. Thanks to the new architecture and increased use of lighter materials such as high-strength steel, the model is 16kg lighter, despite the hatchback version being a whopping 136mm longer. Added to this is the serious work of engineers in the field of aerodynamics. Virtually the entire bottom is covered with aerodynamic panels, a similar role played by the tank, which is offset at the rear and shaped to allow maximum flow. Despite the sharp forms, every detail is carefully considered in terms of aerodynamics - for example, the shape of the front grille, the direction of air to the engine, where many harmful vortices form, or the channels that form air curtains around the wheels.

One of the most high-tech diesel engines on the market

Vibrant vision is an undeniable fact in the new Civic, but in fact the guiding principle in the design of the Civic was efficiency, and after the introduction of completely new generations of three- and four-cylinder turbocharged gasoline engines with a displacement of 1,0 and 1,5 liter diesel engine fits in to this maxim. Although it has brand new technology for a fully hybrid powertrain that operates in the same way as Toyota's, but without planetary gears (using plate clutches), Honda does not intend to abandon the diesel engine in this class. An engineering-intensive company is unlikely to easily abandon a proven, highly efficient heat engine such as a diesel engine.

In terms of performance, the 1,6-liter i-DTEC with 120 hp. did not change. at 4000 rpm and a maximum torque of 300 Nm at 2000 rpm. But this is only at first glance. In the new engine, the engineers replaced the aluminum pistons with steel ones, just like their Mercedes counterparts in the new generations of four- and six-cylinder diesel engines. This achieves several effects. The lower thermal expansion of the steel with increasing operating temperature ensures that the clearance between the piston and the aluminum block is sufficiently large, thereby significantly reducing friction. At the same time, the higher strength of steel compared to aluminum allows for the creation of compact and lightweight pistons, in which there is still a large margin. Last but not least, the lower thermal conductivity of steel leads to a higher temperature of the part, or the combustion chamber, with less heat generation. This not only increases the thermodynamic efficiency, but also improves the ignition conditions of the fuel-air mixture and shortens the combustion time.

And that's not all: other changes to the engine include the stiffening ribs of the aluminum cylinder block, which reduce noise and vibration and increase structural strength. Reducing heating and optimizing cooling results in reduced die wall thickness and thus weight.

The new i-DTEC is based on Garrett's new variable geometry turbocharger and architecture with precise electronically controlled speed. It has lower losses than the unit of the previous engine version. The Bosch injection system uses solenoid injectors with an operating pressure of up to 1800 bar. The high efficiency of the engine is largely due to the intense turbulent air flow created by the spiral channels in the head. Equipped with a nitrogen oxide converter, this machine is also one of the first engines to be tested under Real Emission Conditions (RDE). In addition to the manual transmission, which has typical Honda precision, a nine-speed ZF transmission will be available from mid-2018.

Stand firm on the road

Like the turbocharged petrol engines in the current Civic, the new i-DTEC combines all the benefits of a lighter (base car weighs just 1287 kg) and stronger bodywork, new front and multi-link rear suspension, and excellent brakes that have already proven their worth. quality in auto motor und sport tests. High torque is a prerequisite for all-round driving pleasure, and the long and muffled thump of the diesel engine rather adds to the charm of the sound picture when accelerating. With all the combinations of downsizing, the number of cylinders and deactivating some of them, modern turbo technologies, etc. None of the high tech petrol engines can achieve a real consumption of around 4L/100km with moderate driving. Behavior on the road is also characterized by an indescribable sense of solidity - the car is both precise in handling and extremely stable. The ride is also at a typically high level for the brand.

In the interior, you'll also find a lot of Honda feel, both in the layout of the dash and in the overall quality of the UK-built model. There is a TFT screen in front of the driver with personalization options, and all versions come standard with Honda Sensing's integrated passive and active safety system, including multiple camera, radar and sensor-based assistance systems. The Honda Connect, on the other hand, is part of the standard equipment at all levels above S and Comfort and includes the ability to work with the Apple CarPlay and Android Auto apps.

Text: Boyan Boshnakov, Georgy Kolev