Last week, Mercedes-Benz released a mid-term facelift of the E-Class. In addition to the design changes, the new E-Class is also equipped with a new M254 series engine. You know, in the four years since this generation of E-Class was launched in 2016, its four-cylinder series engines have replaced three generations from M274 to M264 to M254...Do you suffer?
Why did Mercedes-Benz have a third-generation engine in such a short time? What are the highlights of this M254, which will cover the Mercedes-Benz product line in the future? Today we will talk about the story of Mercedes-Benz's three-generation four-cylinder turbocharged engine!
From the timeline, the first release is the M274 engine we are familiar with. In 2012, in order to cope with increasingly stringent emission regulations and emission taxes, Mercedes-Benz began to switch to a new small and medium-displacement engine on the C-class, E-class, and GLK, which is the M274. It is newly developed with 1.6T and 2.0T specifications, matching Mercedes-Benz's latest MRA longitudinal rear drive platform, mainly to replace the old 1.8T and 3.0L V6 engines.
Let’s take the 2.0T version as an example. The actual displacement of the M274 engine is 1991ml, the bore and stroke are 83mm and 92mm, respectively, and the compression ratio is 9.8:1. It can be seen that it is a long stroke, low compression ratio engine, so The setting is mainly to improve the power output of the engine and low torque.
M274 working condition chart
's early introduction of M274 has two power versions, namely the low-power version of 184 horsepower and 300N·m and the high-power version of 211 horsepower and 350N·m. In addition, the M274 uses a low-inertia turbine, which reduces turbo lag and has a faster response speed. Therefore, the M274 engine can output the maximum torque from 1200 rpm and continues to 4000 rpm, which almost covers most of the speed range in daily use.
also benefited from the 2.0T version’s 9.8:1 compression ratio. This engine can also withstand greater turbo pressure. Therefore, M274 also launched a 245-horsepower high-power version in the later period, which is used in C 300 and E 300 And on models such as GLC 300. It is supplemented by the entry-level 1.6T version of the M274 engine, so there are 4 types of power for Mercedes-Benz with M274 engine, 180 (1.6T/156hp), 200 (2.0T/184hp), 260 (2.0T/211hp) And 300 (2.0T/245hp), which meets the needs of most users.
In other technical aspects, the M274 also used the latest third-generation in-cylinder direct injection technology of Mercedes-Benz at that time. The piezoelectric fuel injectors it used could achieve 5 fuel injections in one stroke, while the general level of other engines at the time was 2 injections per stroke. Multiple injections can bring better combustion results, thereby increasing power and reducing fuel consumption. In order to cooperate with the multiple fuel injection system, M274 also uses a multiple spark plug ignition system, which can continuously release 4 sparks within 1ms (1/1000 second).
In addition, M274 also has a very mainstream intake and exhaust variable valve timing system in 2012, CAMTRONIC variable valve lift system, variable displacement oil pump and high-power starter for engine start-stop system. In summary, as an engine launched in 2012, M274 still has certain advantages in technology, especially the excellent low-torque output brought by continuous fuel injection technology and long-stroke design is praised by people.
Infiniti Q50 was pitted by M274
. However, M274 is also accompanied by some quality problems. The first is the abnormal wear of the camshaft. This problem is more common on the old 1.8T M271 engine. The main manifestations are abnormal camshaft angles, engine fault lights, abnormal start and stop, abnormal engine noise, abnormal acceleration, usually tens of thousands The camshaft needs to be replaced. This defect even affects the Infiniti Q50, which also uses the M274 engine, and the scope of influence is still very large. The impact of the
problem is much more than that. The vehicle cannot be started due to a camshaft failure and after repeated attempts to start, the starting motor is short.Lu has triggered a total of 51 spontaneous combustion incidents around the world, 30 of which occurred in the US market. This also triggered the largest global recall of Mercedes-Benz in history. The total number of recalls reached 1 million, involving the three global markets of China, the United States and Germany. Fortunately, the improved M274A engine launched by Mercedes-Benz later has fixed the camshaft problem.
In addition to the hidden danger of spontaneous combustion, the M274 engine also experienced more than one case of cylinder explosion. The cases currently exposed are all caused by the cracking of the internal balance shaft of the engine, which eventually penetrated the cylinder block. Although the above two incidents are just isolated incidents, they undoubtedly laid the groundwork for the early laying off of the M274 engine. Despite this, the M274 won the Ward Top Ten Engines of 2017 by virtue of its status as the head of Mercedes-Benz, and it is also the last glory of the M274 series. Z1z
was only 6 years after M274 was launched, and its successor M264 was born. The brand-new M264 engine has two displacements of 1.5T and 2.0T. Once launched, it quickly replaced the predecessor M274 and became the main medium and small displacement engine of Mercedes-Benz.
Compared with M274, the new M264 engine has been upgraded in many places, among which there are two key technologies. One is that M264 cancels the traditional cylinder liner structure and uses Nanoslide cylinder wall coating technology inside the cylinder wall. This technology sprays a layer of plasma coating inside the cylinder wall to form a protective layer for the cylinder wall, so that the traditional cylinder liner structure is no longer needed.
lacks the cylinder liner structure, the engine has been reduced in weight, and the frictional resistance between the cylinder wall and the piston and the piston ring is reduced by 50%. Of course, this is also a double-edged sword. Because there is no traditional cylinder liner, the internal precision of the engine is required to be higher. Once the piston is eccentrically worn, the entire engine cylinder must be scrapped, which greatly increases the subsequent maintenance cost.
In addition to the changes in the cylinder structure, the main change of the M264 engine is that the whole series can match the 48V light hybrid system, which is also one of the biggest selling points of the M264 series. Speaking of light mixing, we have to say the M264 E15 DEH LA engine, which is the 1.5T engine that was first used on the Mercedes-Benz C 260. The
engine replaces the old M274 2.0T low-power engine. The 184 horsepower remains the same as the old model, but the torque drops to 280N·m, which is 20N·m less than the old model. In addition, due to the smaller displacement of 1.5T, the peak torque platform of the new engine is only in a very narrow range of 3000-4000 rpm, which is completely incomparable with the old M274 outputting maximum torque from 1200 rpm.
So, in order to make up for the shortcomings of the 1.5T engine's low torque and narrow peak torque platform, Mercedes-Benz equipped it with a BSG starter/generator integrated motor, powered by a 48V electrical system and an independent battery pack, and the motor directly drives Engine belt. Compared with the traditional independent design of starter motor and generator, the integrated motor can drive the engine to "ignite" when the flame is turned off, and assist the vehicle to accelerate at low speeds, and can also completely shut down the engine when coasting. The 48V electrical system is used for Steering, braking, and air-conditioning systems supply power, and perform kinetic energy recovery and charging.
However, the power of the BSG motor itself is low, only 10kW, so the auxiliary effect on vehicle power is very small, so the actual power performance of 1.5T+48V is still not as good as the old 2.0T low-power M274 engine.
GLC 260 L uses a 197-horsepower 2.0T engine
. Except for the 1.5T version, the 2.0T M264 is an overall improvement compared to the M274. From the parameters, the low-power M264 2.0T has 197 horsepower and 320N·m. On the GLC 260 L after the mid-term facelift, although the tail is changed to 260, it is actually at the same level as the old GLC 200, and the power parameters are improved compared to the previous 184 horsepower and 300 N·m.
E 300 L uses 258 horsepower 2.0T engine
and looks like C 300, E 300This type of model with the tail label of the 300 series uses a high-power M264 2.0T engine with a maximum horsepower of 258 horsepower and a maximum torque of 370N·m, which is also a certain improvement compared to the old model's 245 horsepower and 350N·m.
GLE 350 is also a 258-horsepower 2.0T engine
, but Mercedes-Benz also has a chicken thief, such as the new generation of Mercedes-Benz GLE, which also uses a 258-horsepower 2.0T engine, but the tail standard has risen to GLE 350! You know, the old GLE 320 uses a 272 horsepower 3.0T V6 engine. After the replacement, the horsepower is less, the cylinder is less, and the tail has risen a lot.
S 320 L uses a 299 horsepower 2.0T engine
. In addition, the new M264 engine also has an ultra-high power version, which is the 299 horsepower, 400N·m version used on E 350, CLS 350 and S 320 models. The version also comes standard with a 48V light-hybrid system, which is the highest level among Mercedes-Benz's vertical 2.0T, and its power output has equaled the old 3.0T V6 engine.
So why has the M264 engine only been used for more than two years, and Mercedes-Benz has launched a brand new M254 engine on the mid-stage facelift E-Class?
The new E-class is equipped with the M254 engine for the first time.
Mercedes-Benz launched the M254 with the mid-term redesign of the E-class. The biggest significance is that the M254 can achieve a higher degree of electrification, which can be understood as Mercedes-Benz's advance layout for the future. Compared with the M274 to M264 "mid-term facelift" upgrade, M254 is more like a complete major upgrade.
M256 3.0T straight six engine
Why do you say that? If we compare the M256 straight-six engine launched at the same time as the previous four-cylinder M264, we can find that the structure of the straight-six M256 is completely different from the four-cylinder M264. The M256 straight-six engine does not have a belt structure (orange above) Box), the air conditioning system is in charge of an independent electric air conditioning pump (blue box above), and the original belt-end BSG motor has been changed to an ISG motor at the flywheel end of the engine.
Left BSG/Right ISG
So what is the difference between this new ISG motor and the previous BSG motor? When talking about M264 before, we said that its BSG motor (simply understood as a belt motor) is connected to the belt of the engine and is responsible for driving the air-conditioning compressor. But this also means that there is an engine between this BSG motor and the gearbox, and the motor cannot independently drive the vehicle. The
ISG motor is located at the engine output terminal
and the ISG motor is moved to the position between the rear end of the engine and the gearbox, so it can independently drive the vehicle, and it also has a response speed comparable to that of an electric vehicle. Therefore, models that use ISG motors will have a significant increase in power response speed. In addition to the power response speed, the new ISG motor has 15kW and 180N·m parameters, which are higher than the old BSG motor, so it has a stronger auxiliary effect for acceleration, kinetic energy recovery and charging power. To put it bluntly, even if the engine is completely turned off, this motor can run with the car.
Beijing Benz's previously announced M254 engine model
is so contrasted, I believe everyone will understand, although the four-cylinder M264 and six-cylinder M256 are engines of the same period, the structure and design concept are completely different. The six-cylinder M256 has obvious technology. Lead a generation. At this time, if we compare the new M254 engine, we can see that the structure of the M254 is very similar to the M256 (even the name is more similar), the beltless (no belt) design is also used, and the electric air conditioning pump and ISG motor are also used. The drive is just a reduction of two cylinders. Compared with the previous generation M264, the biggest upgrade of
's new four-cylinder engine M254 is in this place. The traditional belt structure is cancelled, the position of the motor layout is changed, and the air conditioning system is fully electric. Seeing this, don't underestimate the change of air conditioning electrification, it has very obvious advantages.
Because the traditional air conditioner compressor needs the engine to start the compressor to drive the compressor to run through the belt, it will be more fuel-intensive, and it must be ignited to blow the air conditioner. An air-conditioning system driven independently by a motor can achieve an effect similar to an electric vehicle. The engine can blow the air-conditioning without starting, and the power of the engine will not be wasted, so it will be improved in both comfort and power.
So does M254 have any disadvantages? Since this engine has just been released, we are not good at evaluating its reliability and durability. However, the reason why Mercedes-Benz used the previous four-cylinder M264 to transition, two years later, the same six-cylinder M256 technology was transferred to a brand new one. The four-cylinder M254 also proves that the original design cost of the beltless +ISG motor is relatively high, and the technology is not mature enough, so Mercedes-Benz can only use it on the high-end and niche six-cylinder M256 engine.
Beiben prepared domestically produced M254 as early as 2018.
, but now the M254 has been officially launched in mass production, indicating that Mercedes-Benz has solved the problem of maturity and cost. According to internal documents of Beijing Benz, they have already started the renovation of the domestic M254 engine factory in June 2018, so the layout of Mercedes-Benz for M254 has already begun.
And the significance of M254 to Mercedes-Benz is far more than the present, after all, the technical level of the previous generation M264 has no problem with the current emission regulations. Mercedes-Benz launched the M254 obviously to lay out the future electrification market. Due to the unique ISG motor structure of the M254, the motor can bypass the engine to do work, and the air conditioning system is also independently electronically controlled, so it will be easier to match the PHEV plug-in hybrid system.
Generally speaking, the M274, M264 and M254 engines launched by Mercedes-Benz in the last 8 years actually reflect the changes in the automotive industry in the last 10 years. From large displacement self-priming to small and medium displacement turbocharging, so there is M274. Then countries began to introduce more stringent emission and fuel consumption policies, so Mercedes-Benz also launched an upgraded version of M274 to adapt to the market, M264. In the future, the automobile will be fully electrified, so there is the M254 that has been deployed in advance, and Mercedes-Benz's seemingly "crazy" engine upgrade is actually a change in the development direction of the automobile industry.
AMG GT 53 uses M256+48V light hybrid
. I look forward to driving to C 260 or E 260 with 1.5T M254 engine in the future, because I used the same structure and AMG GT 53 with M256 3.0T straight six engine before. It left a very good impression, and its start-stop system worked very smoothly. According to the information we have received, in the future, this brand new M254 will be used in the domestically produced C-class (expected in the middle of next year), as well as the new E-class and GLC. If you want to experience the latest Mercedes-Benz engine technology, I think this M254 is worth waiting for.
