Some little knowledge about exhaust modification from Elecdeer Auto Parts
How does the exhaust system work?
The function of the exhaust system is to discharge the exhaust gas in the cylinder into the atmosphere with as little exhaust resistance and noise as possible. The exhaust system mainly includes exhaust manifold, exhaust pipe and muffler. Exhaust gas is discharged from the exhaust port connected to the combustion chamber, through the exhaust manifold, the front and middle section of the exhaust pipe (including the three-way catalytic converter) and the tail section of the exhaust pipe (commonly known as the tail row), and finally discharged into the outside air.
The exhaust system reduces the intake resistance and exhaust resistance, increases the pressure in the cylinder, reduces the temperature at the end of the intake air, reduces the pressure of the residual exhaust gas in the exhaust pipe, and increases the area of the intake valve, all of which can improve the volumetric efficiency of the engine and make the engine Power and torque increase accordingly, improving power performance.
The principle is: if the diameter of the exhaust pipe is moderate, the first wave of exhaust gas discharged from the cylinder will press against the inner wall of the exhaust pipe and be quickly discharged downstream after expansion. wave exhaust. When the second wave of exhaust gas is pressed against the inner wall of the exhaust pipe and discharged outward, the low pressure generated behind it is sucking the third wave of exhaust gas, and so on, so that the engine can complete the exhaust action effortlessly, and the exhaust efficiency is also improved. It is also higher than no exhaust system at all, and the exhaust gas remaining in the cylinder is less, and the cylinder can accommodate more fresh air for combustion. Therefore, only by making full use of the back pressure and sucking effect can the exhaust system achieve higher performance.
Classification of modified exhaust pipes
The exhaust pipe is divided into three parts: head section, middle section and tail section. Generally speaking, when we refit the exhaust pipe, we will choose to replace the whole section, the middle tail section, and the tail section.
The first category: the whole paragraph
Replacing the whole section is mainly to increase the diameter of the exhaust pipe to make the exhaust more smooth, and it is easier to exert the horsepower of the car when driving at high speed.
The second category: the middle section
The middle section is usually refitted together with the tail section. The middle section has a three-way catalyst (filtering exhaust gas, environmental protection) and noise reduction. There are many kinds of mid-section modification, some are changed to high-flow three-way such as competitive three-way, and some are removed. Three-way (for The environmental pollution is huge), and the silencer is removed and changed to a straight-through. These have a better effect on horsepower improvement, and the sound will be louder, but will lose low torque.
The third category: tail section
The tail section is the position of the silencer drum and tail throat. The modification here is often to replace it with a small silencer drum, or directly remove the silencer and match it with a beautiful tail throat. The sound of such modification is relatively explosive and very loud, but this Modification of the mid-end section.
It is worth mentioning that for the cracking sound of the tail throat, an exhaust valve can be installed. The function of the exhaust valve is to control the exhaust sound wave and the exhaust back pressure.
Exhaust modification changes
1. Changes in appearance: For example, the exhaust pipe of some cars is unilateral, but after changing the exhaust pipe, it becomes bilateral. One is to show personality, and the other is to show grade. Because the larger the displacement and the more luxurious the car, the more exhaust pipes. Some cars look much better when matched with a good-looking large rear lip bumper and exhaust pipes.
2. Changes in power: Changing the exhaust can basically increase the horsepower, and the smooth exhaust system will inevitably improve the efficiency of the engine.
3. Changes in sound: The biggest benefit of changing the exhaust is the change in sound waves. Showing off the high-pitched exhaust sound can attract people's attention and directly express our different value pursuits.
4. Changes in material life: As long as the quality is excellent, the materials and service life of the modified exhaust are much higher than those of the original car exhaust. Of course, as long as it is not a particularly cheap car, the exhaust system of the original car is still acceptable, and it will not be a problem to use it for five or eight years.