Lectures on the basic knowledge of power modification of car modification

one,Spark plug: Change the ordinary nickel-copper spark plug with low cost, short life of 20,000 kilometers, poor high temperature resistance, and low ignition energy to a long life of 100,000 kilometers, high temperature resistance above 2000°C, strong ignition ability, but correspondingly higher cost The iridium metal spark plug is a way to get started. It is necessary to pay attention to the choice of heat resistance value. If it is too low, the engine will be unable to accelerate, and if it is too high, it will produce carbon deposits. Naturally aspirated vehicles use Japanese 5 degrees to 7 degrees to achieve the purpose of strengthening, turbocharged cars are better than 7 degrees.

2. Light flywheel: If the flywheel that is responsible for the balance is too heavy, it will affect the re-acceleration. Replace the light flywheel to get a good acceleration response, and the oil-separation coordination must be more accurate.

3. Large-flow air filter: Increase the engine's vital capacity and reduce the air intake resistance. The effect of filtration and heat insulation is also very good. It is a must-have for the primary modification.

Four,High-voltage line: Replace the high-resistance live wire, which is usually about 5,000 ohms, from the original car to a low-resistance live wire to makeIgnition coilsThe released energy is transmitted to the spark plug to the greatest extent, but beware of flashover, interference and other symptoms.

5. Pooley plate: There are many places where light can be stolen in the engine room.publicThe well-known lightweight Puli disk is one of them.The original Pulipan is mostly made of cast iron. ForCrankshaftIt is not a small burden, replacing aluminum alloy materials can reduce the weight by more than half, andCamshaftPlymouth can also replace the lightweight version. As for the replacement of lightweight Puli, there will be problems with idling air-conditioning and rapid shrinkage. As a result of the author's questioning of the "boss" of Gretel, as long as the diameter of the lightweight Puli does not shrink, such a situation will not occur.

6. Ignition enhancer: all know to proceedCar modificationTime, most will touch the engine’sIgnition systemIn the past, it was more common to change the sub-cylinder line and spark plugs to high-performance products, but the ignition capability that may be improved is quite limited. For the ignition system to stably ignite the mixed gas with increased pressure in the cylinder after the modification, people need more powerful products.

7. Exhaust: Exhaust system modification can becarFor the entry point of modification, almost 100% of the cars mainly modify their own cars, and almost all of them are exhaust systems. However, there are several car owners who will pay attention to the knowledge. At this stage, most of the modified exhaust systems are for appearance, and the exhaust sound of "throat, throat" running on the street is really quite irritating. ! This time I will talk about exhaust modification, so that all car owners who want to modify it have a more rational understanding.

The exhaust system is basically composed of five parts:

1. The part connected to the exhaust port of the engine cylinder head is calledExhaust manifold, Commonly known as dead air banana, the function is to collect the exhaust gas flowing through the exhaust port of the cylinder head, so that it can be discharged smoothly;

2. After that is the role of environmental protection "Three-way catalytic converter"You don’t need to talk about the role to know, just because your car won’t be intercepted all day long for exhaust gas testing and fined;

3. After that is the FRONT SILENCER. If it is used in a racing car, it should be said that the role of the middle drum is not great, and it can even be cancelled. However, if it is a modification of a street car, it is simply to reduce the row. Resonance phenomenon during breath;

4. Shouweiguan is called the exhaust drum (REAR SILENCER), commonly known as the dead gas hose, and it is also considered the most modified part at present.

Exhaust system modification, to put it plainly, is to reduce exhaust back pressure. The definition of back pressure is academically: becauseexhaust pipeThe internal pressure hinders the force of the exhaust pulse.Reducing back pressure actually makes the alternating between suction and exhaust smoother, which is equivalent to prolongingValveOverlap time. To modify the exhaust system, you should start with the middle and the tail. This concept is known to domestic modifiers, but many shops will take it for granted how to do it, or no matter how much it is, just say it loudly. In fact, from the (drum) to the tail (drum) modification, the key lies in the tube design. The design can be divided into "short and thick", which means that the length of the tube is minimized and the diameter is increased. This modification does not It is not suitable for daily driving, because the back pressure is low and the exhaust gas flow rate is slow at the middle and low rotations, which causes the mixed gas in the cylinder to be exhausted without combustion. The torque performance at the middle and low rotations is naturally poor, but at the high rotation, the pulse is dense and high. The exhaust is smooth, and the horsepower increases greatly; the other is the "slender type", the modification is only to change the material of the tube body, without changing the original curved shape, and even the tail section is slightly thinner. The advantage of the reform is that it is suitable for daily urban driving, the pressure in the pipe is high, the exhaust gas can be discharged quickly, and the torque at low and medium speeds has increased, but the horsepower at high speeds is not flattering. As for the tail drum, there are nothing more than two forms. One is called the reflex type. Most of the original tail drums are in this form, but the problem is that the resistance is large and the power loss is serious; the second is the linear type, and the principle is very simple. The inlet and outlet are basically in the same straight line. The sound-absorbing method is purely dependent on sound-absorbing cotton and end-cutting. Almost all modified tail drums adopt a straight line. Therefore, before changing the middle to the end, it is best to adapt to your daily needs and driving habits to be wise.

After changing the middle to the end, it should be the three-way catalytic converter. Its function is to slow down the flow rate of exhaust gas and form resistance. However, there are many problems encountered in changing the catalytic converter in China. For example, the use of fake catalytic converters has good performance and low price. However, if the exhaust gas is caught and needs to be inspected, the exhaust gas must be unqualified! But if it is replaced with a real modified catalytic converter, the price is very expensive. Although the performance will be greatly improved compared with the original factory, it is really not everyone can afford or be willing to consume it. More than 10,000 yuan to 20,000 yuan is a normal price. .

Dead air banana is considered the most important part of the exhaust system modification, and the effect is the most obvious. The original dead bananas are generally made of cast iron. Some car manufacturers use stainless steel. For example, BMW. The original exhaust bananas are produced in large quantities, so not only the inner wall is rough, but the length of the exhaust manifold may not be the same. As a result, the phenomenon of so-called exhaust interference occurs. Therefore, why there are very few modified dead bananas for BMW cars on the market? I think a big reason is because the original BMW products are already made of stainless steel, and the quality is already very high and high-performance.

The dead bananas used for refitting are generally made of stainless steel, which is nothing more than taking advantage of its several advantages: good high temperature resistance; thin wall, so the overall weight is light; although the inner wall of the stainless steel tube does not need to be polished and slipped. However, it is much smoother than the original pig iron products, which is conducive to the movement of exhaust gas; in addition, it is easy to bend and cut, and it is easy to achieve the purpose of equal length. Especially in the case of NA to TURBO, stainless steel will inevitably be used. Qijiao is for easy accommodation.The equal length of the manifold length actually has a positive effect on the horsepower improvement. Theoretically, the working sequence and time of each cylinder is the same. If the length of the exhaust pipe is different, the exhaust efficiency of each cylinder will definitely deviate and decrease. In addition, there is a pressure difference between the manifolds. The final result must be chaotic exhaust pulses, and the horsepower and torque output will naturally decrease. On the TURBO engine, academically, it is to make the exhaust side as much as possible. The turbine blades are subject to quantitative, smooth, and continuous attacks, making the turbine workRotating speedThe upper limit, efficiency, and stability are greatly improved, so that the boost pressure can be increased.

The first batch, FRONT PIPE, is the section of exhaust pipe that connects the dead gas banana to the three-way catalyst (turbine engine is from the exhaust side air outlet to the three-way catalyst). The part of NA cars that fewer people will modify, because the effect is not obvious. But if you modify the exhaust of a TURBO engine, you will basically replace the first batch. Why? This is because it is related to another proper noun: secondary exhaust pressure. Quite simply, the turbine blades are driven by exhaust gas. The smoothness of the exhaust in this section directly affects the working speed and limit of the TURBINE. The principle is a bit like the dead banana in the NA car.

The modified dead banana can basically overcome the shortcomings of the original banana. Although the modified dead banana has many advantages, but the price is high, like a modified dead banana used in AUDI TT 1.8T, the price is as high as RMB 16,000 yuan, this price is really not affordable for ordinary people, so some cheap products appeared on the market. Inexpensive products cannot be said to have no effect at all, and there will definitely be a little effect, but whether it can maximize its effect is another matter. Why some brands can sell so much more expensively? Except for the import channel factor, it is very big. To a certain extent, it is caused by the high cost of testing. The test is not as simple as measuring the position. If it is true, just buy some stainless steel pipes and then bend them and sell them! What engineers are needed there, and what engine test benches are there?

Exhaust systems on the market mostly refer to tail drums, because there are many people who modify them, and the price is not too expensive. There are deals for cheap ones of several hundred yuan, but those products are not supported by test data, and the actual use effect goes to No one can really tell what the point is. I believe that those shops who advertise how many horses can be improved, when they ask him to take the data, it is the same. There are basically several types of exhaust modification parts available on the market: The first type is domestically produced. For example, X Xun, which is famous in Hong Kong and moved to China, is a representative of it. The price is not expensive. They are all at the level of thousands of dollars. The quality is average but they are better than the styles. Basically, they have corresponding products for the models that can be bought in China. If you open a model that has been eliminated abroad, such as the JETTA . However, I have never used it personally, and it is difficult to estimate the level of their design strength. However, some friends around me said that they are at an intermediate level. Of course, in the level of modified parts, the intermediate level must be better than the original.

The second is the Japanese modified brand. There are two types of Japanese brands. One is the original modified car manufacturer's products, such as MUGEN, NISMO, TRD, etc., which have their own corresponding models or car series. This exhaust system is very complete, and basically it is installed at the time of installation. Just loosening the screws, it’s easy to disassemble and assemble. The performance can be fully matched to the performance characteristics of the original engine itself. Therefore, the torque at low and medium revolutions is also significantly improved while the horsepower is maximized. The premise is that there is no need. Change other parts of the engine. The other is the product of a comprehensive refitting component manufacturer. There are many brands, such as 5 ZIGEN, APEXi, BLITZ, FUJITSUBO, ARC, ESPRIT, IMPUL, PRODRIVE, TANABA, HKS, RSR, TRUST, TOP SECRET and even famous air force kits. VEIL SIDE has exhaust products. However, I personally feel that when choosing the exhaust pipes or systems from these factories, it is basically necessary to install the vehicle after a heavy modification (FULL OPTION). There are many out-of-design designs, but the shortcomings are outstanding sound, insufficient torque, and emphasis on improving horsepower. It may not be a good thing for running on the street all day long. Coupled with price factors, fewer people in China install Japanese modified brand products. Furthermore, maybe there are very few Japanese performance cars that can be modified in China.

The third type is the European and American series. American products are a bit like Japanese products. The exhaust sound is loud and loud, and the Americans are really happy to do it themselves when they change their cars. Therefore, the only well-known exhaust brands in the United States are BORLA and so on. Family. European brands are not like Japan. Basically, only the few factories that make exhaust systems are the most familiar REMUS, SEBRING, which is more famous than REMUS in Europe, and the lower-end SUPERSPRINT, etc., which are modified in Europe. The atmosphere of the car is so high that it can almost be described as "modified for the whole people", but the models modified by the European refitting factories are more specific. Computers, suspension, braking, body aerodynamic kits, interior trims, etc. are all available. But in fact, many parts are OEM after processing. It seems that the dead gas hoses of OETTINGER, AC, and HAMANN will find REMUS OEM after completing the design by themselves, but in statutory business Morally, although REMUS has the same model of exhaust system sold on the market, its style will be different from that sold by the foundry, and the price of the two will also differ, and it will even be more expensive than the modified brand. In terms of performance, the exhaust drums modified from European products will have a solid sound and full bass, so if you hear a BORA exhaust sound that is extremely low and coherent on the street, then it must be a European product.