Another eternal topic on the Internet. Or has the issue of battles and disputes been resolved? I now go to the "mechanics". And in general on the "machine" never went. But in search of a new car, he set his sights on the "automatic". Many advise, however, a significant part of advisers dissuade with arguments that the "automatic" is more expensive when buying, during operation and has significant inconveniences.
Let's discuss the pros / cons of the "machine".
First, what do you drive?
I am currently reading this article on the subject:
Myths from the depths of centuries
Sometimes there are statements about the high speed of switching "mechanics". This is completely wrong, more precisely, it has been wrong for twenty years now. Previously, “automatic” really took a very long time to switch, but the manual transmission progresses slowly, and the automatic transmission progresses quickly.
Mechanics cannot compare with the switching speed of preselectives or modern hydraulic automata. Even if it's a cam box that goes "up" almost instantly. After all, part of the switching in the automatic transmission occurs without breaking the power flow, and the rest take place in hundredths of a second. As long as the box is good, of course.
Still often fans of "mechanics" extol the possibility of fine work of the clutch as a huge advantage. Forgetting that a box with sufficient dynamic range and fast shifting simply does not need all these games, it can get better traction characteristics without too much friction burning.
Yes, and off-road, it often turns out that the "buildup" with the manual gearbox is no more effective than the same technique on the "automatic" - with an increase in the switching speed, this advantage has disappeared.
A little about the dynamics with the MCP
Claims of a special “feel for the car” when driving with a manual gearbox are so common that they almost do not cause objections. It seems that the use of manual gearboxes in motorsport already suggests that here it is - the top of engineering for powerful machines, providing better control.
There is one nuance: the manual transmission is prescribed by the rules of racing, and as soon as the rules are relaxed, the racers suddenly begin to install automatic and semi-automatic gearboxes. Yes, and "sequential" with cam gear, which are used on serious sports cars, are very far removed from civilian transmissions in terms of switching speed, reliability and resource.
What are the positive driver qualities of the MCP? The only thing that makes manual shift boxes more "sporty" in behavior is the transfer of control over all the nuances of control to the driver, who knows where the car will go, how much traction he needs, how much revs he needs ... And at the same time, the driver anticipates a change in the traffic situation.
The ability of any electronics to predict the actions and wishes of the driver will always lag behind his thoughts. Just do not forget that now not only the “mechanics” are switched forcibly. Almost all modern multi-speed automatic transmissions (and even, imagine, CVTs!) Have a “manual” mode of operation for those modes when the driver understands better what needs to be done. And many have also acquired very convenient paddle shifters, which can correct the automatically selected gear to the desired one for five or six seconds without any extra actions. For example, on a Mercedes A-class or a modest Suzuki SX4 New.
The manual mode of the automatic transmission in 99 cases out of 100 is enough to complete the maneuver. And if you need to keep the transmission "until the last", that is, there are a lot of cars with such an "honest" manual mode of the box, only this functionality is usually not very much in demand. As you can see, forced switching has not been a monopoly of the MCP for many years now, numerous “automatic machines” have learned to copy this function even better. Unless specific control methods with a complete shutdown of traction by pressing the clutch and starting from high speeds remain with the manual gearbox.
Human factor
But the disadvantages of "mechanics" can be listed for a long time. For starters, it usually has a smaller dynamic range, that is, the ratio of the minimum and maximum gear ratios. If you expand the dynamic range, you will have to increase the number of gears, and the operation of the engine in intermediate modes will already be inefficient. Six gears in a modern passenger car is a reasonable maximum that a driver can operate. Any increase in the number of gears is useless. The average driver simply won't use them all. Truck drivers with more than a dozen gears do not always shift optimally, and in fact there the requirements for shifting speed are much lower than for cars.
The notorious "overclocking to a hundred" dictates its requirements. Most cars now reach “hundreds” in second gear, but if another shift is required, then the car loses its dynamics sharply, and the consumer who appreciates this parameter very much (probably drives to work like this every day) immediately twists his mouth in a displeased grin. In fact, this means that the manufacturer simply cannot make the first gears shorter, and the “mechanics” are not able to fully use the engine power when accelerating at speeds of 0-120 kilometers per hour. Yes, and sharp starts are necessarily accompanied by the smell of a burnt clutch, the gear ratios of the first gear simply do not leave other options for an intensive start.
At the moment of switching, a break in the power flow and torque jumps are inevitable. This means that the car loses at least a little in the dynamics of acceleration, and the drive wheels can break into a slip. And the more powerful the engine, the more serious this problem. Yes, it’s not for nothing that Mercedes back in the 90s refused to install “mechanics” on cars with a capacity above 193 hp. With. It was not so much an ideological as a technical solution. As soon as progress in the development of the AKP made it possible to move away from the MCP, it was abandoned.
Even on low-power engines, the need to drop traction to zero at the time of a gear change is a problem, especially when you need to accelerate sharply. You will have to plan shifts in advance or lose precious fractions of a second (or maybe whole seconds) to switch and reach the “working” engine speeds. And even worse: for turbocharged engines, the turbine pressure also has time to drop, which worsens performance.
With powerful motors, wheel slip is possible in second or third gear after shifting, with the inevitable loss of stability by the car. The desire to shift faster causes even stronger torque surges and shocks in the transmission, which can cause damage to both the manual gearbox itself and failure of the drive shafts, differential and universal joints. It is not for nothing that AvtoVAZ allows robotic boxes to work with more powerful motors than manual shift boxes with the same “stuffing”. The robot is just more accurate! And this problem is called "human factor".
People get tired and make mistakes. This is an indisputable fact that cannot be corrected. They also make mistakes when shifting gears. And let an experienced driver do all the operations almost automatically, quickly and absolutely accurately. But after 50 such switches, he will get tired. There will be inconsistency in his actions, or he will do everything slower than he could, well, or the shocks in the transmission will become too strong.
In any case, he will not use the mechanics to 100%. That's why riders try to install automated boxes whenever possible - this simply reduces the dependence of the results on the condition of the rider and allows him to focus on the result.
Just do not nod your heads those who could not master the manipulation of the clutch and lever - the athletes have a much higher load on the driver and the requirements for the quality of switching than the city "racers". For the average driver, the "human factor" in relation to the manual transmission means only the inability to understand the principles of the transmission, poor fine motor skills and inattention to the control process. However, the result is the same, adjusted for the class. Either shifts will be slow, or the car will twitch like a frog under current due to shocks in the transmission.
Margin of safety
Reliability, which is usually presented as a great advantage of the manual transmission, is in fact only a reserve for unsuccessful actions of the driver, which generate torsional vibrations with a moment several times greater than the engine torque. Slips, drifts and light tuning for supercharged engines quickly take the entire stock to zero, and even faster than in the case of automatic transmissions, because there is no gas turbine engine, which dampens torsional vibrations perfectly. And no dampers can compare with it.
True, the MCP is a little easier to provide with a large margin of safety and is much easier to replace with a stronger one, if one exists. So installing the most durable manual transmission is still a better way to handle the load than adapting a stronger automatic transmission for a tuning car. But in drag racing, the automatic transmission is very popular, because the two-, three-speed design is configured for maximum power and run-out, the work is much simpler than full-fledged debugging in all driving modes.
Real, not imaginary advantages of mechanics
If it seems to you that I have just criticized the "mechanics" to smithereens, then you are mistaken. I just didn't mention those advantages of the MCP that remain with it until the very end, and which are rarely mentioned.
Weight and size characteristics are often very important, and they are traditionally better for “mechanics” than for most “automatic machines”. This parameter is especially important on lightweight sports cars, where every kilogram counts, and a larger transmission may simply not fit. The progress of the AKP has made these benefits less noticeable, but they still exist.
"Mechanics" is not limited in speed, which is important for highly accelerated engines. But “automatic machines” with gas turbine engines cannot work effectively at speeds above six to seven thousand - drive losses increase catastrophically, and oil can simply break the “donut” or disable it. But the new “preselectives” with friction clutch, dry or in an oil bath, do not have a gas turbine engine and related restrictions.
The MCP has a very high efficiency due to the use of rolling bearings and low losses to drive the oil pump or splash lubrication. Any "machine" has slightly higher internal losses. Even "dry" preselectives cannot yet catch up with the classic two-shaft manual gearboxes, not to mention the three-shaft ones. And hydromechanics lags behind even more - the losses for the operation of the oil pump and the heating of the oil will always be in it. But even here the advantage has already been reduced to a minimum.
"Mechanics" does not depend on oil pressure and electronics, which means that it is much less likely to fail immediately, and its components are less interconnected. The failure of one of the gears has almost no effect on the operation of the others. Critical failures happen less often in the "iron" design. There is nothing to oppose here to the automatic transmission - the more modern the design, the “thinner” its device. Now even an error in the ATF temperature sensor can lead to improper operation, and any contamination of the valve body leads to progressive mechanical failures.
The manual gearbox does not require complex adaptations to the motor and machine. If the gear ratios are suitable and there is a torque margin, then you can set it. A minimum of contact points with on-board electronics, all other settings are in the driver's head. The automatic transmission at least requires “implantation” into the standard electrical system and docking with the electronic control unit, from which it receives data on the temperature of the motor and air, as well as torque. For ideal functioning, complex finishing work is also required, only then the driving characteristics of the automatic transmission will be higher than that of machines with mechanics - there will be no unnecessary switching, engine overload and the dynamics will become good. We'll have to work on the automatic transmission cooling system.
It is usually more difficult to sort out the MCP, but on the other hand, this is a purely plumbing task that does not require understanding in electronics and hydraulics, complex diagnostics, etc. The master is required to simply assemble the knot, adhering to the dimensions and tightening torques - that's all. With quality parts. You only need experience with similar mechanisms, and all the nuances are already taken into account in the design itself.
The repair of a modern “machine” is often a task that requires “electronic” diagnostics to start - the scanner reads the sensor readings of the box and adapts its “brain”, runs tests of the electronic control system. And only then you can disassemble and change something. With normal disassembly, it is not a fact that the problem will be identified. Often, the hydraulic unit for a complete diagnosis of a malfunction must be placed on a special stand that measures pressure at different points under various operating modes. In general, without special knowledge and tools, many breakdowns simply cannot be eliminated.
What is the result?
MECHANICS:
Advantages of a mechanical box
1) The accelerating dynamics of a car with ordinary mechanics is better than that of an automatic. With it, you can spin the engine up to the “red zone”, but the automatic will start shifting gears at a certain speed (unless, of course, you are driving in manual mode), so the acceleration dynamics is several seconds faster than that of the automatic.
2) With a certain driving skill and fast gear shifting, as well as with the skill to start the car in coasting, you can achieve decent fuel economy, it will be difficult for your opponent to do this. Automatic transmission - it is generally not recommended to turn on neutral speed while driving.
3) Requires less oil than the opponent. In an automatic transmission, you need to pour from 6 to 10 liters of gear oil. In the mechanical about 3 liters.
4) In winter, the car is easier to start. Firstly, there is less oil in the box, and secondly, when you press the clutch pedal, you kind of disconnect the gearbox from the engine, respectively, the load when starting the engine is reduced.
5) Repair. The mechanical option is much cheaper to repair, and almost any, even non-official companies can do it.
6) Last, winter driving. On a car with mechanics, you can safely slip in the snow, on a machine it is not desirable, the transmission oil can overheat.
Cons of mechanics
1) So, the first minus is the convenience of driving. Novice drivers get used to the mechanics for a very long time. They are especially bad at “starting off in a car”, as well as moving from a place to a rise.
2) Clutch. Novice drivers on cars with a manual transmission can easily burn the car's clutch due to inexperience. And this is already an expensive repair; this will not happen with a competitor according to the principle.
3) Engine resource. The engine life is much lower. This is because the machine will not let you "force" the engine, spin it to the limit.
MACHINE
Cons of an automatic transmission
1) The classic version accelerates more slowly than mechanics
2) It has only 4 speeds (classic version), and the mechanics are already five.
3) Again, the classic version, consumes more fuel
4) More oil in the building
5) In winter it is more difficult to start
6) The cost of the car is more expensive, by 30 - 40 thousand rubles
6) The cost of repairs is more expensive.
Advantages of the machine
I want to talk about the pros in more detail, because the machines are different and you shouldn’t lump them together, so to speak.
1) Acceleration is different. Yes, the classic torque converter automatic at 4 speeds is slower than mechanics. But now there are CVTs and types for 6 and 7 - steps with two clutch discs, they are no longer inferior in efficiency, and sometimes surpass it. For example, the CVT is superior to the mechanics, as is Volkswagen's DSG automatic.
2) Classic (4-re gears) consumes more fuel, but if you take modern automatics or CVTs (for 6 or continuously variable transmissions), then their fuel consumption is already much lower, sometimes even lower than on mechanics.
3) The convenience of driving a car is much higher. Even an inexperienced driver will be able to calmly move away without nerves and jerks, without creating an emergency.
4) The resource of the engine and transmission units is much higher - it controls the speed and will not allow the engine to overheat.
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