Today we're going to talk about boosting traction. car engine during certain critical situations, in particular about the reserve of power that is created before emergency action and about the maximum torque that reduces the inertia of the engine. As experienced drivers say driving instructors Today we will talk about peregazovka.
Regassing and maximum thrust
Regassing is an increase in engine speed in neutral or with the clutch depressed at speed before the next gear is engaged. To prepare the car and increase the speed in advance for a sharp start or a quick maneuver.
Many novice drivers believe that overdrive is a legacy of older cars that didn't have synchronizers. But at driving instruction we are often told that re-gassing has not lost its relevance in modern car models, especially to improve safety at various critical moments through the use of car engine power.
Another way to help drivers cope with a difficult situation on the road is the maximum traction of the car's engine or torque. It can be achieved at one or another frequency of rotation of the automobile crankshaft. This indicator is usually indicated in the technical specifications for the vehicle. For example, for VAZ cars, the maximum engine thrust is approximately 4000 rpm.
In simple terms, it is best to overcome some critical situations when the speed is higher or corresponds to the highest torque. In this case, the engine responds much faster to pressing the gas pedal. If the speed decreases, then a sharp throttling will no longer give a quick effect.
Note that today (in most cases due to high fuel prices) the so-called “economical” driving is very relevant, which is why motorists emergency situations are less likely to help themselves with engine power.
Learning to increase power?
To increase the power of the car engine to the desired level, various techniques are used. For example, the standard regassing before downshifting. This technique is relevant in the following cases:
- before entering the turn;
- before overtaking;
- on the rise;
First you need to turn off the clutch, and then sharply press on the gas and release it sharply, which will bring the frequency value closer to the maximum torque value when the crankshaft rotates. A reserve of 1000-1500 revolutions is also made here, which will be lost when the gear is engaged. Further, during the regassing, we turn on the downshift using the clutch, and then press the gas pedal.
Re-acceleration by double pressing the clutch is used if there are any defects in the gearbox (for example, damage to the synchronizers), when two switching cycles are missed and when shifting gears when driving on a very slippery pavement. To do this, stop the gas supply and turn off the clutch, then “open” the gas again, which will increase the speed. Then turn off the gas and clutch again, while a downshift is needed. After that, "open" the gas.
Re-gassing in neutral is important before shifting into a low gear with a skip and during heavy acceleration, that is, when power drops sharply. In order to perform this re-acceleration, you need to turn off the gas and clutch, shift to “neutral”, “open” the gas (this will increase the speed and give some reserve), shift into low gear, and then press the gas.
After-gas, if you need to upshift, is used by drivers to compensate for some loss of speed, for example, due to a long pause during upshifting. This method is also applicable when switching gears with one or another pass (II - IV or I - III). In aftergassing, you need to follow this sequence of actions. First, disengage the clutch and shift into neutral. Then, sharply, quickly, but very dosed, we “open” and “close” the gas, after which we turn on the overdrive. At the end, we “open” the gas again.
A few words about high-speed regassing ...
High-speed regassing, when there is slippage of the clutch and a downshift, or rather its inclusion, but in a shock way, is used in those extreme situations when there is no time to perform actions.
Such a relocation is carried out in the following way. As soon as the engine starts to lose speed (although it is better to start the procedure even before that), slowly disengage the clutch with a slight delay, while keeping the throttle open. This gives the engine the ability to rev up quickly. Just at this moment, you need to downshift and press the clutch. I must say that the delay in disengaging the clutch causes it to slip and increases the speed in a short period of time, and to any level.
Clutch slip when in constant gear is used to boost power when there is no time to downshift. This method can be used when overcoming a steep slope (its peak), a section with dirty and loose soil, when driving on snow. Incomplete disengagement-engagement of the clutch gives an additional 300-600 revolutions, which accelerates the vehicle.
Note that all of the above methods have a fairly wide range of applications, both in critical traffic situations, as well as in standard. They allow you to increase the controllability and stability of the machine due to the anti-lock effect during emergency braking. In addition, these techniques are designed to form a reliable engine thrust, which reduces the severity of critical situations.
Video on how to do regassing and selection of speed:
Good luck and peace on the road!
The article used an image from the site www.kakprosto.ru
Do you want the car to buck? Turn on low!
Downshifting is a little more difficult than upshifting. If you are a novice driver and this is not obvious to you, do the following: accelerate to 50 km / h in third gear, shift into second gear and quickly release the clutch pedal as usual. As a result, the tachometer needle will jump up sharply, and the car will twitch great. Try it! Happened?
This will always be the case when shifting from high to low gear, only the intensity of the jerk will be different depending on the speed and gear. Why is there a breakthrough? As the sharply “bouncing” tachometer needle shows us, when the gear is lowered, the engine speed increases. If when switching from II to 3rd gear arrow drops from 3500 to 2500 rpm, then when switching from III to II, on the contrary, it jumps from 2500 to 3500. This means that including downshift, we forcibly accelerate the motor to more high speed. Since the rotating parts of the engine are heavy, inert, they resist spin-up, which is expressed in the jerk of the car. It turns out that a jerk is like a protest of the motor :)
Regassing or clutch?
So I recommend that you regularly, every time you downshift, use the throttle and preferably with double depressing the clutch pedal. With the help of re-gassing, you will change gear faster, smoother and safer for both traffic, and for car parts than with a smooth release of the clutch pedal. Of course, it’s difficult to master gas recirculation, but if you do it, then, I’m afraid, you will like it, so much so that you won’t tear it off! And then you won’t be imprisoned for an automatic machine :)))
Toe Forever!
By the way, the overdrive (in English: toe) came to us from the good old fifties, from trucks that did not have synchronizers and it was impossible to turn on the gear without overdrive in principle. Therefore, today sometimes there is a point of view that, they say, regassing is an anachronism, greetings from the past, and that any modern car handles downshifts well without over-revving. If you think so, then let's go back to the second paragraph of this article and once again turn on the lower gear without re-gassing. And for greater clarity, let's switch to 50 km / h not in second, but immediately in first gear. Just choose a quieter and wider place on the road, otherwise you will fly off the road, it won’t seem enough ...
I will also add that re-gassing is an integral part of the arsenal of tricks of any professional racer. So if you are planning to get into sports driving, gas recirculation is a must for you! Try it, keep it up!
And if you need practice - come to the courses "Magic of shifting" or "Driving on a race track". For novice drivers, the City Driving course is more suitable, and for advanced drivers, I can also advise you to take our school's exclusive course: MBA Driver's Course: Driving Mastery.
Even if you are not going to comprehend the heights of racing driving, in any case, gas is an element of driving skill and the calling card of a competent driver. Recommend!
With shifting and downshifting - everything, and in the next article I will finally tell you
Everyone who drives a car is quite rightly sure that he knows how to do it. But how rationally do we drive our car? In today's Driving School lesson, we will talk about when to shift gears.
Why was checkpoint invented? The answer to this question can be obtained if you listen to the motor while driving at the same speed, but in different gears. The lower the stage, the higher the speed at which this pace is maintained. That is, at the same speed, each of the gears corresponds to its own engine speed. And vice versa - at the same engine speed, the car gets the opportunity to develop different speeds. The gearbox just allows you to use the engine in the speed range that is most beneficial in terms of its maximum output or economy.
Move on schedule
The "golden mean" of switching should be sought in the rpm range corresponding to the maximum torque and maximum power (see graph). It is the first parameter that determines the intensity of the acceleration of the machine.
Experiments and calculations of designers show that for passenger car with an eight-valve gasoline engine with a volume of 1.0 - 2.5 liters, acceleration is optimal with shifts to a higher gear at speeds close to the maximum torque - about 3000 - 4000 per minute. At the same time, the accelerator should be pressed about half of its stroke - opening the throttle to a larger angle increases fuel consumption, but saves a minimum of time.
A little more energetic
Fans of a more energetic “drive” (within reason, of course) can move the switching point of the next gear three to four hundred revolutions higher, and push the pedal down to two-thirds of the way.
In a simple and understandable form for every driver, these graphics and calculations can be expressed in terms of the speed of the car, so the instructions for the car usually stipulate maximum speed movement in every gear. For example, in cars with engines of 1.2 - 2.0 liters and a five-speed gearbox during normal driving in first gear, it is not recommended to exceed the speed of 30 - 35 km / h, in the second - 45 - 60 km / h, in the third - 90 - 95 km / h, on the fourth - 110 - 130 km / h. Manufacturers allow a short-term excess of these indicators by 10 - 15 km / h when overtaking or on climbs. This means that the tachometer needle (if it is in the car) can be “driven” into the red zone of the scale for 10-15 seconds.
Uniform movement
Maintaining the optimum engine speed when driving without acceleration and deceleration is determined by the same principles as during acceleration. Excessively low or high speeds are undesirable and even harmful.
Driving at low speeds requires more frequent gear changes, since with the slightest increase in load, you need to move to a lower gear. At the same time, by maintaining higher revs in a lower gear, the driver "saves" one shift and has more power to accelerate.
However, the positive aspects of driving in lower gears at high speed - the ability to shift less often or more better dynamics- offset by excessive fuel consumption and resource reduction power unit.
"A special case"
When accelerating on a steep hill, shifting should be done a little later than usual, because while driving with the transmission disengaged (with the clutch depressed), the car will have time to lose more speed than on flat terrain or a gentle slope.
slowdown
When decelerating, competent motorists shift from higher to lower gear in the same rev range (see graph) when the engine is at its most powerful. The main thing is to turn on the lower stage on time, not allowing the crankshaft speed to fall below the limit, beyond which the motor no longer has a reserve of torque for a subsequent increase in speed.
Tachometer to the rescue
For rational driving, it is useful to learn and remember two specifications from your vehicle's owner's manual. Firstly, the engine speed at which maximum torque is achieved, and secondly, the speed at which the engine develops the highest power.
Acceleration will be most vigorous if you use the right gear and accelerator to keep the revs in the immediate vicinity of maximum torque and maximum power.
The maximum possible speed is achieved in the highest engine power mode.
Naturally, you should not drive with your eyes fixed on the tachometer in order to keep the arrow near the jagged numbers. It is enough to get used to the sound of the engine, corresponding to the given speed, and learn how to automatically shift gears exactly at the right moment, fixed by memory.
On cars without a tachometer and with good sound insulation, experienced drivers feel when the car should change gear by the reaction of the car to pressing the gas pedal, by the rise and fall of acceleration.
Misconception #1: "economic"
Some drivers abuse short accelerations - without letting the engine spin up, they immediately move up to the next gear. Someone explains this by the desire to save the engine and gasoline, someone wants silence in the cabin and thus avoids the roar that the engine emits.
Meanwhile, switching up too early during acceleration, when the engine speed has not yet reached the maximum torque, only has a negative effect. The motor wears out more intensively due to low pressure oil and increased loads on the parts of the cylinder-piston group. In addition, with such a ride, fuel consumption increases, since in order to continue acceleration from low revs in each next higher gear, you have to press the gas pedal harder to open throttle valve to a larger angle.
It is also unprofitable to delay the acceleration process with a small throttle opening - a third of the pedal travel or less. Any acceleration requires the supply of an increased portion of fuel, so its extension inevitably leads to an increase in fuel consumption. Time, of course, is also not saved.
Less noise
-Limited "agility" of the machine (for low-power models of a small class)
-Increased engine wear
-Excessive fuel consumption
-More frequent switching
Misconception #2: "sporty"
Many drivers suffer from another "ailment" - the habit of "twisting" the motor during acceleration. Like, we drive in a sporty way, and the athletes know how dynamics and speed are achieved.
But in urban conditions, such a manner would be more correctly called nervous. Fuel from such drivers intensively flies "down the pipe", but the main thing is that the goal - driving "in a sporty way" - is still not achieved. Modern motors very high-speed and differ in the maximum moment shifted to the region of high revolutions. But it makes no sense to “turn” the engine above the highest power speed - there will be an increase in dynamics compared to the optimal mode, but small. In addition, “extra” crankshaft revolutions lead to a reduction in the resource of engine parts and an increase in fuel consumption.
Despite the fact that this is an extremely rare choice of gear when driving a car, there are still situations in which there is a need to shift to the first speed (gear), which is preferable for faster acceleration while the car is moving, although such a shift will be associated with certain additional difficulties. .
Shifting gears can become an automotive art for drivers and they fully understand exactly what actions form smooth transitions between gears, engine speeds and different shaft speeds in. And despite the fact that the first gear, by its nature, is designed solely to move the car, the hairpins are very sharp turns multiplied by the steepness of the hill may require the driver to change into a gear with a higher torque ratio, namely, the first gear of the gearbox.
If you dear friends (motorists) have tried to switch to first gear (speed) in this way before, you may have noticed for yourself how difficult it is to “stick” first gear at speed, up to that very clang under the hood of the car and even at full squeeze clutch. We will immediately reassure you that everything is in order with your favorite car, the box has not broken, the synchronizers have not crumbled. Everything is very simple, you need to know and master the special technique of switching to the lowest speed (gear).
In ordinary life, this situation with the transition to 1st gear occurs precisely when the motorist, at the entrance to the traffic light, actually just stopped his car at a red light and here suddenly the green traffic light lights up for him when the car needs to move quickly. The second gear of the box will pull the car almost out of place for a long time, then by hook or by crook you will need to immediately turn on the first reduced speed (gear), here and at that very moment the knowledge that we we want to provide you today in this article.
Technically, the problem itself is that the difference in ratios between second and first gears is quite (too) large. Therefore, it is far from always possible for synchronizers to successfully cope with this task to fill this very gap. Synchronizing devices in first gear have to work much harder than in other gears, which can certainly lead to their early failure and indispensable.
In essence, the actions of synchronizers themselves can be compared to a small clutch that is installed on the output shaft between the gears to slow down or increase relative to the speed of the gears, which perform the actions (work) of lightly meshing the teeth in the gear. Therefore, it turns out that when an attempt is made to shift to first gear, then at that very moment the relative speed between the output shaft and the input shaft will be excessively high (large), compared to other different and less relative speeds (gears).
An example is the transmission of a car. Honda Civic 2016. The ratio for first gear in this box is 3,6:1 which means that for every 3.6 complete revolutions of the crankshaft, the gear makes only one revolution. 2nd gear has a ratio 2,1:1 , the 3rd gear ratio is 1,4:1 , 4th gear with ratio 1:1 direct gear, in 5th gear the ratio is 0,8:1 , and the last 6th gear has the ratio 0,7:1 .
As you can see friends, the difference is in gear ratio gear teeth become smaller and smaller as they move up to higher gears, which in turn makes it easier for the synchronizers to match the speeds of the gears.
However, similar and similar problems can occur not only when switching from second to first gear.
For example, you need to overtake vehicle, and there is insufficient distance to the solid line. You are moving in fourth gear and have already begun to bypass the vehicle being overtaken. You need to accelerate quickly. The only logical way in this situation for you would be to shift to a lower gear.
And the third? It is unlikely that the car needs more intense acceleration. An experienced driver, comparing at this moment the speed and engine speed, can instantly come to the conclusion that it is necessary to turn on the second speed. OK. But there is one “but”, to do this without a clear understanding of the actions performed by the driver will be very, very difficult and which will be extremely harmful for the box itself. Therefore, friends, remember that there are certain and correct solutions for the safe performance of overtaking transport actions.
They (actions) can be divided into two main groups: double clutch release and regassing .
They allow you to equalize the speed of rotation of the crankshaft and reduce the load on the synchronizers in gear, which will contribute to smooth switching. *
*Despite the effectiveness of these methods, we still do not recommend their regular use, especially in those moments when you shift into first gear, since it will still not work to reduce shock loads as much as possible and the transmission will still receive additional stress.
Double clutch release
You can read more about this shifting technique in our article: - "Here (in this article) we will outline and tell you about the basic postulates of gear shifting technique.
Summarizing the process of downshifting from fourth to third gear:
- 1. Press the clutch pedal.
- 2. We move the shift lever to the neutral position.
- 3. Release the clutch.
- 4. Click on the throttle.
- 5. Press the clutch pedal again.
- 6. We switch to third gear.
- 7. Release the clutch pedal.
There are many types of peregazovaniya. Its initial use was due to the lack of synchronizers in the variable gearbox, which excluded their smooth inclusion. Today, re-gassing is used for smoother engine speed changes when downshifting at high speed. In cases of lowering, a large load acts on the engine and gearbox, which can adversely affect performance.
How to do a peregazovka?
- With a standard peregazovka on the rise, before overtaking, in a turn, we reset the fuel supply and squeeze the clutch. Without stopping in the neutral position, lower it.
- We sharply press and release the accelerator pedal and briefly increase the fuel supply. We bring the engine speed to the value of the maximum torque. Release the clutch and open the throttle.
- When lowering through the gear, turn off the fuel supply to the engine, squeeze the clutch. We turn on the neutral gear and bring the engine speed to the value of the maximum torque with a margin for switching on a lower gear.
- Shift into low gear and release the clutch pedal. We increase the fuel supply.
- When extreme situation We use high-speed reflow. Before the engine begins to lose speed, holding the throttle open, slowly engage the clutch.
- At the moment of a sharp rise in speed, we turn on a lower gear and clutch. By delaying the disengagement, you cause the clutch to slip, which will allow you to raise the speed of the crankshaft to the level you need.
- Applying peregazovka to compensate for the loss of speed when upshifting, turn off the clutch, move the gear knob to the neutral position. Sharply, but in doses, we increase and decrease the fuel supply. We turn on the increased gear, remove the foot from the clutch pedal and open the fuel supply.