|
3-stage VTEC
Three-stage VTEC is a multi-stage implementation of Honda's VTEC and VTEC-E (colloquially known as dual VTEC) technology, implemented in some of the company's D series engines from 1995 to the present day, allowing the engine to achieve both fuel efficiency and power. VTEC-E (for "Efficiency") is a form of VTEC that closes off one intake valve at low RPMs to give good economy at low power levels, while "VTEC" is a mode that allows for greater power at high RPMs, while giving relatively efficient performance at "normal" operating speeds. "Three-stage VTEC" gives both types in one engine, at the cost of greater complexity and expense. Stage 1 – 12-valve VTEC-E VTEC-E (economy) was designed to achieve better fuel economy, at the cost of performance. The engine operates in "12-valve mode", where one intake valve per cylinder in the 16-valve engine remains mostly closed to attain lean burn. The lean burn mode gets the air to fuel ratio above the 14.7:1 stoichiometric ratio and thus ena ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VTEC
VTEC (Variable Valve Timing & Lift Electronic Control) is a system developed by Honda to improve the volumetric efficiency of a four-stroke internal combustion engine, resulting in higher performance at high RPM, and lower fuel consumption at low RPM. The VTEC system uses two (or occasionally three) camshaft profiles and hydraulically selects between profiles. It was invented by Honda engineer Ikuo Kajitani. It is distinctly different from standard VVT (variable valve timing) systems which change only the valve timings and do not change the camshaft profile or valve lift in any way. Context and description Japan levies a tax based on engine displacement, and Japanese auto manufacturers have correspondingly focused their research and development efforts toward improving the performance of their smaller engine designs. One method for increasing performance into a static displacement includes forced induction, as with models such as the Toyota Supra and Nissan 300ZX which used t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Honda D Engine
The Honda D series inline-four cylinder engine is used in a variety of compact models, most commonly the Honda Civic, CRX, Logo, Stream, and first-generation Integra. Engine displacement ranges between 1.2 and 1.7 liters. The D Series engine is either SOHC or DOHC, and might include VTEC variable valve lift. Power ranges from in the Logo to in the Civic Si. D-series production commenced 1984 and ended 2005. D-series engine technology culminated with production of the D15B 3-stage VTEC (D15Z7) which was available in markets outside of the United States. Earlier versions of this engine also used a single port fuel injection system Honda called PGM-CARB, signifying the carburetor was computer controlled. D12 series engines (1.2 liter) D12A * Found in: ** 1986-1988 Honda City GG (Japanese Market) *** Displacement: 1237 cc (75.5 cu in) *** Bore and Stroke: 72 mm x 76 mm (2.83 in x 2.99 in) *** Compression: 9,5:1 *** Power: at 6,500 rpm *** Torque: at 4,00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel Efficiency
Fuel efficiency is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier (fuel) into kinetic energy or work. Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile. Non-transportation applications, such as industry, benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion, such as ammonia production during the Haber process. In the context of transport, fuel economy is the energy efficiency of a particular vehicle, given as a ratio of distance traveled per unit of fuel consumed. It is dependent on several factors including engine efficiency, transmission design, and tire design. In most countries, using the metric system, fuel economy is stated as "fuel consumption" in liters per 100 kilometers (L/100 km) or kilometer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intake Valve
A poppet valve (also called mushroom valve) is a valve typically used to control the timing and quantity of gas or vapor flow into an engine. It consists of a hole or open-ended chamber, usually round or oval in cross-section, and a plug, usually a disk shape on the end of a shaft known as a valve stem. The working end of this plug, the valve face, is typically ground at a 45° bevel to seal against a corresponding valve seat ground into the rim of the chamber being sealed. The shaft travels through a valve guide to maintain its alignment. A pressure differential on either side of the valve can assist or impair its performance. In exhaust applications higher pressure against the valve helps to seal it, and in intake applications lower pressure helps open it. The poppet valve was invented in 1833 by American E.A.G. Young of the Newcastle and Frenchtown Railroad. Young had patented his idea, but the Patent Office fire of 1836 destroyed all records of it. Etymology The word p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cylinder (engine)
In a reciprocating engine, the cylinder is the space in which a piston travels. The inner surface of the cylinder is formed from either a thin metallic liner (also called "sleeve") or a surface coating applied to the engine block. A piston is seated inside each cylinder by several metal piston rings, which also provide seals for compression and the lubricating oil. The piston rings do not actually touch the cylinder walls, instead they ride on a thin layer of lubricating oil. Steam engines The cylinder in a steam engine is made pressure-tight with end covers and a piston; a valve distributes the steam to the ends of the cylinder. Cylinders were cast in cast iron and later in steel. The cylinder casting can include other features such as valve ports and mounting feet. Internal combustion engines The cylinder is the space through which the piston travels, propelled to the energy generated from the combustion of the air/fuel mixture in the combustion chamber. In an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lean Burn
Lean-burn refers to the burning of fuel with an excess of air in an internal combustion engine. In lean-burn engines the air:fuel ratio may be as lean as 65:1 (by mass). The air / fuel ratio needed to stoichiometrically combust gasoline, by contrast, is 14.64:1. The excess of air in a lean-burn engine emits far less hydrocarbons. High air–fuel ratios can also be used to reduce losses caused by other engine power management systems such as throttling losses. Principle A lean burn mode is a way to reduce throttling losses. An engine in a typical vehicle is sized for providing the power desired for acceleration, but must operate well below that point in normal steady-speed operation. Ordinarily, the power is cut by partially closing a throttle. However, the extra work done in pumping air through the throttle reduces efficiency. If the fuel/air ratio is reduced, then lower power can be achieved with the throttle closer to fully open, and the efficiency during normal driving (b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air To Fuel Ratio
The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing for liquid water to exist on the Earth's surface, absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation). By mole fraction (i.e., by number of molecules), dry air contains 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere. Air composition, temperature, and atmospheric pressure vary with altitude. Within the atmosphere, air suitable for use in photosynthesis by terrestrial plants and breathing of terrestrial animals is found only in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stoichiometric
Stoichiometry refers to the relationship between the quantities of reactants and products before, during, and following chemical reactions. Stoichiometry is founded on the law of conservation of mass where the total mass of the reactants equals the total mass of the products, leading to the insight that the relations among quantities of reactants and products typically form a ratio of positive integers. This means that if the amounts of the separate reactants are known, then the amount of the product can be calculated. Conversely, if one reactant has a known quantity and the quantity of the products can be empirically determined, then the amount of the other reactants can also be calculated. This is illustrated in the image here, where the balanced equation is: : Here, one molecule of methane reacts with two molecules of oxygen gas to yield one molecule of carbon dioxide and two molecules of water. This particular chemical equation is an example of complete combustion. St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rev Limiter
A rev limiter is a device fitted in modern vehicles that have internal combustion engines. They are intended to protect an engine by restricting its maximum rotational speed, measured in revolutions per minute (RPM). Rev limiters are pre-set by the engine manufacturer. There are also aftermarket units where a separate controller is installed using a custom RPM setting. A limiter prevents a vehicle's engine from being pushed beyond the manufacturer's limit known as the redline (literally the red line marked on the tachometer). At some point beyond the redline, engine damage may occur. Operation Limiters usually work by shutting off a component necessary for the combustion processes to occur. Compression-ignition engines use mechanical governors or limiters to shut off electronic fuel injectors. A spark-ignition engine may also shut off fuel or stop the spark ignition and some just reduce the engine's power by changing the spark timing. In the case of an automatic transmission ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable Valve Timing
In internal combustion engines, variable valve timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with variable valve lift systems. There are many ways in which this can be achieved, ranging from mechanical devices to electro-hydraulic and camless systems. Increasingly strict emissions regulations are causing many automotive manufacturers to use VVT systems. Two-stroke engines use a power valve system to get similar results to VVT. Background theory The valves within an internal combustion engine are used to control the flow of the intake and exhaust gases into and out of the combustion chamber. The timing, duration and lift of these valve events has a significant impact on engine performance. Without variable valve timing or variable valve lift, the valve timing is the same for all engine speeds and conditions, therefore compromises are neces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Honda Engines
is a Japanese Public company, public multinational corporation, multinational Conglomerate (company), conglomerate manufacturer of automobiles, motorcycles, and power equipment, headquartered in Minato, Tokyo, Japan. Honda has been the world's largest motorcycle manufacturer since 1959, reaching a production of 400 million by the end of 2019, as well as the world's largest manufacturer of internal combustion engines measured by volume, producing more than 14 million internal combustion engines each year. Honda became the second-largest Japanese automobile manufacturer in 2001. In 2015, Honda was the eighth largest automobile manufacturer in the world. Honda was the first Japanese automobile manufacturer to release a dedicated luxury brand, Acura, in 1986. Aside from their core automobile and motorcycle businesses, Honda also manufactures garden equipment, marine engines, personal watercraft, power generators, and other products. Since 1986, Honda has been involved with artifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.png "Click for more on -> Cylinder (engine)")
