Compare NA engine with turbine engine.

Natural intake (NA) engines will appear in the form of single turbine, double turbine or even four turbines with low intake efficiency at high speed, with the same working purpose, process and principle. Simply speaking, its principle is nothing more than using the high-temperature and high-speed exhaust gas generated by the engine after the explosion stroke to flow into the exhaust side turbine through a specially shaped downcomer to drive the turbine blades on the exhaust side to rotate. At the same time, the gas compressor impeller coaxially connected with the turbine blades on the exhaust side will compress the gas flowing through this type, and the compressed gas will become fresh air with a certain pressure and high density after being cooled by the intercooler. Natural air intake owners who advocate horsepower, if they want to increase horsepower. The solution is to increase the engine displacement, increase the cylinder compression ratio, and increase the throttle. In fact, the above modification method has limited effect.

If you want to go further, you must replace the high-angle camshaft, but replacing the high-angle camshaft will bring a lot of troubles to daily use, such as unstable belt speed, easy death, inability to use air conditioning at low speed, too much torque loss at low speed, and high fuel consumption. The main trouble of refitting a naturally aspirated car is that it is much more expensive to increase the power of 65,438+000 horses than a turbo car, so this is the most important thing.

There are several parts that need to be modified when the natural intake engine is equipped with turbine: 1 exhaust head section, 2 turbine body, 3 exhaust front section, 4 intake cooler (also known as intercooler), 5 high-strength pipeline, 6 oil supply computer, 7 intake system and 8 pressure reducing valve. The above are the necessary parts for converting a natural air intake vehicle into a turbine vehicle. If you want to go further, you can add an oil cooler. The installation of turbine must first have a turbine head part (banana-shaped) that meets the specifications of exhaust head part. As far as the kits on the market now are concerned, they are all open mold casting. This kind of pouring riser has uniform section specifications and good wall thickness, strength and structure. But most people pay little attention to the casting head, and generally use cast iron, so the price can be reduced. However, cracks are more likely to occur due to long-term thermal expansion and cold contraction, so some manufacturers simply use white iron alloy components for casting once and for all. This head is expensive, but it hasn't broken after years of testing. There is also a manual welding joint, which was originally used to upgrade and modify the turbine joint, hoping to achieve the effect of equal length and equal flow. However, due to the large bending angle and many interfaces, it is necessary to weld in sections. Although it has the advantage of perfect curve, fracture is the most difficult problem under the erosion of high pressure and high heat of steam turbine. This high output head part is just not durable.

Using high-tech numerical control pipe bender, the required elbow is manufactured at one time, directly from the exhaust port to the turbine inlet, so that the elbow part has no weld at all, and the inner diameter is smooth and there will be no cracks. Unfortunately, this kind of production technology can be described as aristocratic practice, and it cannot be customized for a single model. Only a large factory can place an order for molds, so it is estimated that the types of cars must be limited and the price is extremely expensive. The turbine is connected below the head section, and the size of the turbine depends on the amount of air blown. Simply put, it is a smaller turbine, which acts earlier and starts faster. Generally speaking, when driving in urban areas or when self-propelled vehicles are driving at low speed, smaller turbines should be preferred. When do you need to upgrade a larger turbine? Generally speaking, there are two situations. One is that the existing turbine can no longer maintain high-grade and high-load pressurization, that is to say, the pressure value of the turbocharger pressure gauge will drop at high speed, that is, the amount of gas blown by the turbine at high speed is not enough for the engine to suck in, so the gauge pressure of the pressure gauge will start to drop, which is equivalent to the fact that the turbine body can not maintain enough gas volume at full load, and the turbine needs to be replaced to achieve the pressurization value required by the driver. The other is to improve the acceleration ability. To put it bluntly, more air is blown into the cylinder at the same time. However, when the engine is running at low speed, the engine will lag because the exhaust gas discharged from the cylinder is not enough to make the turbine reach the maximum supercharged state. This phenomenon will be more obvious after the turbine is enlarged, which is a very troublesome problem for driving. Then, if the exhaust pipe of a naturally aspirated car is modified, the problem of back pressure must be considered to avoid losing too much torque. However, for the turbine car, the exhaust turbine blade is the manufacturer of exhaust back pressure, because the high-temperature and high-pressure exhaust gas released by the exhaust valve directly impacts the turbine exhaust impeller, and then is guided by the exhaust front pipe to the middle exhaust pipe for discharge, so that the exhaust turbine blade will not be blocked by the exhaust gas and cannot continuously accept the new exhaust gas impact in time. In normal mode, the turbine pressure will naturally increase by about 0. 1kg after replacing the upgraded exhaust front section or reducing the front section angle, which proves that the resistance behind the exhaust impeller will really affect the performance of the turbine. As far as the kits on the market are concerned, it is best to choose the front section manufactured by mold opening, which has better inner wall smoothness, less difficulty in maintenance and disassembly, and easier to maintain in the future.