The internal combustion process is downright cruel, and the piston is indeed on the front line of the battlefield. The nature of converting mutual energy into rotational force means that the four-stroke process attempts to eject the pistons from the cylinder deck and blow them continuously through the oil pan. At 6,000 rpm, this melee drops 100 times per second. In addition, advances in the cylinder head and valve train technology have enabled modern engines to increase speed and build more pressure in the cylinders than ever before. The most important thing is that forced induction and nitrous acid usually aggravate the beating. In recent years, with the increase of ethanol content and the decrease of octane number, the quality of pumped gas has declined.
Given these terrible circumstances, it is really surprising that piston failures are so rare nowadays. Although what is called a “warhead” shows that the piston is nothing more than an old forged aluminum block, the technology involved in its development is shocking. The piston design is more than simply ramming the aluminum ingot into a cylindrical shape and finishing it. Some design elements of the Pistons tend to fascinate hot rods, and other factors that most people don’t even realize may be the difference between being a hero and exploding. With the easy horsepower and high RPM potential of the Gen III / IV small cylinder block, choosing the right piston is an important step in the successful design of any engine combination. Here is a complete Piston Guide for ls Engines.
Piston Skirt
Essentially, the piston skirt allows the piston to perform its primary and secondary movements. The main movement of the piston is from top dead center to bottom dead center and back to top dead center. The second movement is the effect of the piston swinging in the hole. The rolling effect is caused by friction and viscous resistance, the position of the piston’s center of gravity, changing lateral loads, and temperature changes.
In order to control skirt wear, reduce parasitic power loss, and improve ring seals, piston manufacturers must accurately predict secondary motion pistons. it is necessary to optimize the contact area and the oil path into the area. Two methods to reduce the contact area include reducing the length of the skirt and changing the shape of the skirt surface. Reducing the skirt length will reduce friction, but will increase the secondary motion effect that affects the ring seal. Changing the shape of the skirt is more effective because it can reduce the contact area and secondary movement.
Power Pistons
The power adder piston naturally aspirated engine structure is much more than the combination of forced air and nitrous oxide. Therefore, most standard pistons are designed for naturally aspirated engines. Although forged pistons are very sturdy, power adder applications require ultra-sturdy pistons designed for pressurization and nitrous acid. The main difference between a naturally aspirated engine and a nitrogen or blower engine is the cylinder pressure and operating temperature, so it is very important to design the piston accordingly. Higher pressure requires the piston to have a thicker crown and higher structural rigidity. In addition, the diameter of the wrist pins needs to be thicker, and the rings need more tension to make them thicker and more durable.
Customized Pistons
Due to the infinite combinations of hole diameter, stroke crank, connecting rod length, cylinder block deck height, cylinder head, and power adder that can be integrated into the engine design, in some cases, the ideal piston cannot be used as an engine. Forging of the shelf. Fortunately, piston manufacturers are more than happy to make custom pistons for their specific applications, and the cost is not much higher than that of standard pistons. The manufacturing process of the piston is highly automated. CNC machine tools carve the forging into the final shape of the piston. Therefore, a custom piston set only costs an additional $100, and in some cases, its cost may be the same as the catalog piston. In addition, some piston companies can replace a set of customized warheads within a day or two. In contrast, custom connecting rods and connecting rods are astronomically expensive, which makes it much easier to design the piston around the rest of the rotating assembly and the short block than the other way around.
Read More: Used Transmissions
Piston Coating
In recent years, engine manufacturers have begun to test the advantages of applying coatings to various engine components, including pistons. They are usually used in the top and piston skirts to protect aluminum from severe internal combustion effects. The use of thermal barrier coating on the piston crown helps maintain surface hardness and resist surface corrosion and pitting caused by explosions. The coating also allows the piston to last longer at high temperatures. Although the top coating is beneficial to the piston, engine manufacturers must also consider the impact of the coating on the rest of the engine. Because less heat is dissipated through the piston and the top-coated piston ring, this means that the heat will be reflected elsewhere in the combustion chamber. This additional heat can adversely affect the combustion chamber, valve surfaces, and exhaust ports, which may require coating. In contrast, skirt linings help reduce wear, surface friction, and cold start wear. In some cases, a skirt can also be used to safely reduce the gap between the piston and the cylinder wall.
