In an internal combustion engine, the cylinder head sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber and this joint is sealed by a head gasket. In most engines, the head provides space for the passages that feed air and fuel to the cylinder, the head can be a place to mount the valves, spark plugs, and fuel injectors. With a chain drive to a camshaft, the extra length of chain needed for an overhead cam design could give trouble from wear. Early sidevalve engines were in use at a time of simple fuel chemistry, low octane ratings and this made their combustion chamber design less critical and there was less need to design their ports and airflow carefully. One difficulty experienced at this time was that the low compression ratio implied a low expansion ratio during the power stroke, exhaust gases were thus still hot, hotter than a contemporary engine, and this led to frequent trouble with burnt exhaust valves. A major improvement to the engine was the advent of Ricardos turbulent head design.
This reduced the space within the chamber and the ports. Most importantly, it used turbulence within the chamber to thoroughly mix the fuel and this, of itself, allowed the use of higher compression ratios and more efficient engine operation. Despite common knowledge, the limit on performance is not the gas flow through the valves. With high speed engines and high compression, the limiting difficulty becomes that of achieving complete and efficient combustion, efficient engines thus tend towards the pent roof or hemi designs, where the valves are brought close in to the centre of the space. Where fuel quality is low and octane rating is poor, compression ratios will be restricted, in these cases, the sidevalve engine still has much to offer. Such engines remained in production into the 1990s, only being replaced when the fuels available in the field became more likely to be diesel than petrol. In the overhead valve design, the head contains the poppet valves. In the overhead camshaft design, the head contains the valves, spark plugs and inlet/exhaust tracts just like the OHV engine.
The number of heads in an engine is a function of the engine configuration. Almost all inline engines today use a cylinder head that serves all the cylinders. A V engine has two heads, one for each cylinder bank of the V
Intercoolers increase the efficiency of the induction system by reducing induction air heat created by the supercharger or turbocharger and promoting more thorough combustion. This removes the heat of compression occurs in any gas when its pressure is raised or its unit mass per unit volume is increased. A decrease in intake air charge temperature sustains use of a more dense intake charge into the engine, the lowering of the intake charge air temperature eliminates the danger of pre-detonation of the fuel/air charge prior to timed spark ignition. This preserves the benefits of more fuel/air burn per engine cycle, the inter prefix in the device name originates from historic compressor designs. In the past, aircraft engines were built with charge air coolers that were installed between multiple stages of forced induction, thus the designation of inter, modern automobile designs are technically designated aftercoolers because of their placement at the end of the supercharging chain. In a vehicle fitted with two-stage turbocharging, it is possible to have both an intercooler and an aftercooler, the JCB Dieselmax land speed record-holding car is an example of such a system.
In general, an intercooler or aftercooler is said to be a charge-air cooler, intercoolers can vary dramatically in size and design, depending on the performance and space requirements of the entire supercharger system. Common spatial designs are front mounted intercoolers, top mounted intercoolers, each type can be cooled with an air-to-air system, air-to-liquid system, or a combination of both. Turbochargers and superchargers are engineered to force more air mass into an intake manifold. Intercooling is a used to compensate for heating caused by supercharging. Increased air pressure can result in a hot intake charge. Increased intake charge temperature can increase the cylinder combustion temperature, causing detonation, excessive wear. Passing a compressed and heated intake charge through an intercooler reduces its temperature and pressure, if the device is properly engineered, the relative decrease in temperature is greater than the relative loss in pressure, resulting a net increase in density.
This increases system performance by recovering some losses of the inefficient compression process by rejecting heat to the atmosphere, intercoolers that exchange their heat directly with the atmosphere are designed to be mounted in areas of an automobile with maximum air flow. These types are mainly mounted in front mounted systems, side-mounted intercoolers are generally smaller, mainly due to space constraints, and sometimes two are used to gain the performance of a larger, single intercooler. Air is directed through the intercooler through the use of a hood scoop, in the case of the PSA cars, the air flows through the grille above the front bumper, through under-hood ducting. Top mounted intercoolers sometimes suffer from heat diffusion due to proximity with the engine, warming them, some World Rally Championship cars use a reverse-induction system design whereby air is forced through ducts in the front bumper to a horizontally mounted intercooler. Because FMIC systems require open bumper design for optimal performance, the system is vulnerable to debris
Gasoline direct injection
Directly injecting fuel into the combustion chamber requires high-pressure injection, whereas low pressure is used injecting into the intake tract or cylinder port. In some applications, gasoline direct injection enables a stratified charge combustion for improved fuel efficiency. GDI has seen rapid adoption by the industry over the past years. The major advantages of a GDI engine are increased fuel efficiency, emissions levels can be more accurately controlled with the GDI system. The cited gains are achieved by the control over the amount of fuel. In addition some engines operate on full air intake and this means there is no air throttle plate, which greatly improves efficiency, and reduces piston pumping losses. It eliminates air throttling losses in some GDI engines, when compared with conventional fuel-injected or carbureted engines, the engine management system continually chooses among three combustion modes, ultra lean burn and full power output. Each mode is characterized by the air-fuel ratio, the stoichiometric air-fuel ratio for gasoline is 14.7,1 by weight, but ultra lean mode can involve ratios as high as 65,1.
These mixtures are much leaner than in an engine and reduce fuel consumption considerably. Ultra lean burn or stratified charge mode is used for light-load running conditions, at constant or reducing road speeds, the fuel is not injected at the intake stroke but rather at the latter stages of the compression stroke. The cavity creates the effect so that the small amount of air-fuel mixture is optimally placed near the spark plug. This stratified charge is surrounded mostly by air and residual gases, which keeps the fuel, decreased combustion temperature allows for lowest emissions and heat losses and increases air quantity by reducing dilation, which delivers additional power. This technique enables the use of mixtures that would be impossible with carburetors or conventional fuel injection. Stoichiometric mode is used for moderate load conditions, fuel is injected during the intake stroke, creating a homogeneous fuel-air mixture in the cylinder. From the stoichiometric ratio, an optimum burn results in a clean exhaust emission, full power mode is used for rapid acceleration and heavy loads.
The air-fuel mixture is homogeneous and the ratio is slightly richer than stoichiometric, the fuel is injected during the intake stroke. It is possible to inject more than once during a single cycle. After the first fuel charge has been ignited, it is possible to add fuel as the piston descends, the benefits are more power and economy, certain octane fuels have caused exhaust valve erosion
Turbochargers were originally known as turbosuperchargers when all forced induction devices were classified as superchargers. Nowadays the term supercharger is usually applied only to mechanically driven forced induction devices, compared to a mechanically driven supercharger, turbochargers tend to be more efficient, but less responsive. Twincharger refers to an engine with both a supercharger and a turbocharger, turbochargers are commonly used on truck, train and construction equipment engines. They are most often used with Otto cycle and Diesel cycle internal combustion engines and they have been found useful in automotive fuel cells. Forced induction dates from the late 19th century, when Gottlieb Daimler patented the technique of using a pump to force air into an internal combustion engine in 1885. During World War I French engineer Auguste Rateau fitted turbochargers to Renault engines powering various French fighters with some success, in 1918, General Electric engineer Sanford Alexander Moss attached a turbocharger to a V12 Liberty aircraft engine.
Turbochargers were first used in aircraft engines such as the Napier Lioness in the 1920s. Ships and locomotives equipped with turbocharged diesel engines began appearing in the 1920s, turbochargers were used in aviation, most widely used by the United States. During World War II, notable examples of U. S. aircraft with turbochargers include the B-17 Flying Fortress, B-24 Liberator, P-38 Lightning, and P-47 Thunderbolt. Turbochargers are widely used in car and commercial vehicles because they allow smaller-capacity engines to have improved fuel economy, reduced emissions, higher power, in contrast to turbochargers, superchargers are mechanically driven by the engine. Belts, chains and gears are common methods of powering a supercharger, for example, on the single-stage single-speed supercharged Rolls-Royce Merlin engine, the supercharger uses about 150 horsepower. Yet the benefits outweigh the costs, for the 150 hp to drive the supercharger the engine generates an additional 400-horsepower, a net gain of 250 hp.
This is where the principal disadvantage of a supercharger becomes apparent, another disadvantage of some superchargers is lower adiabatic efficiency as compared to turbochargers. Adiabatic efficiency is a measure of an ability to compress air without adding excess heat to that air. Even under ideal conditions, the compression process always results in elevated temperature, however. Roots superchargers impart significantly more heat to the air than turbochargers, for a given volume and pressure of air, the turbocharged air is cooler, and as a result denser, containing more oxygen molecules, and therefore more potential power than the supercharged air. In practical application the disparity between the two can be dramatic, with turbochargers often producing 15% to 30% more power based solely on the differences in adiabatic efficiency. By comparison, a turbocharger does not place a direct mechanical load on the engine, although turbochargers place exhaust back pressure on engines, in contrast to supercharging, the primary disadvantage of turbocharging is what is referred to as lag or spool time
Internal combustion engine cooling
Internal combustion engine cooling uses either air or a liquid to remove the waste heat from an internal combustion engine. For small or special purpose engines, air cooling makes for a lightweight, the more complex circulating liquid-cooled engines ultimately reject waste heat to the air, but circulating liquid improves heat transfer from internal parts of the engine. Engines for watercraft may use open-loop cooling, but air and surface vehicles must recirculate a fixed volume of liquid, heat engines generate mechanical power by extracting energy from heat flows, much as a water wheel extracts mechanical power from a flow of mass falling through a distance. Engines are inefficient, so more heat energy enters the engine comes out as mechanical power. Internal combustion engines remove waste heat through cool intake air, hot exhaust gases, Engines with higher efficiency have more energy leave as mechanical motion and less as waste heat. Some waste heat is essential, it guides heat through the engine, much as a water wheel works only if there is some exit velocity in the water to carry it away.
Thus, all heat engines need cooling to operate, Cooling is needed because high temperatures damage engine materials and lubricants. Cooling becomes more important in when the climate very hot. Internal-combustion engines burn fuel hotter than the temperature of engine materials. Engine cooling removes energy fast enough to keep temperatures low so the engine can survive, some high-efficiency engines run without explicit cooling and with only incidental heat loss, a design called adiabatic. Such engines can achieve high efficiency but compromise power output, duty cycle, engine weight, most internal combustion engines are fluid cooled using either air or a liquid coolant run through a heat exchanger cooled by air. Marine engines and some engines have ready access to a large volume of water at a suitable temperature. The water may be used directly to cool the engine, but often has sediment, which can clog coolant passages, or chemicals, such as salt, engine coolant may be run through a heat exchanger that is cooled by the body of water.
Most liquid-cooled engines use a mixture of water and chemicals such as antifreeze, the industry term for the antifreeze mixture is engine coolant. Some antifreezes use no water at all, instead using a liquid with different properties, such as propylene glycol or a combination of propylene glycol, most air-cooled engines use some liquid oil cooling, to maintain acceptable temperatures for both critical engine parts and the oil itself. Most liquid-cooled engines use air cooling, with the intake stroke of air cooling the combustion chamber. An exception is Wankel engines, where parts of the combustion chamber are never cooled by intake. There are many demands on a cooling system, one key requirement is to adequately serve the entire engine, as the whole engine fails if just one part overheats
The Maserati Quattroporte is a four-door sports luxury saloon produced by Italian car manufacturer Maserati. The name translated from Italian literally means four doors, there have been six generations of this car, with the first introduced in 1963, and the current model launched in 2013. The original Maserati Quattroporte was built between 1963 and 1969 and it was a large saloon car powered by V8 engines—both firsts for a series production Maserati. The task of styling the Quattroporte was given to Turinese coachbuilder Pietro Frua, while the design was by Frua, body construction was carried out by Vignale. The Quattroporte was introduced at the October-November 1963 Turin Motor Show, the Tipo 107 Quattroporte joined two other grand tourers, the Facel Vega and the Lagonda Rapide, capable of traveling at 200 km/h on the new motorways in Europe. It was equipped with a 4. 1-litre V8 engine, producing 260 hp DIN at 5,000 rpm, Maserati claimed a top speed of 230 km/h. The car was exported to the United States, where federal regulations mandated twin round headlamps in place of the single rectangular ones found on European models.
Between 1963 and 1966,230 units were made, in 1966, Maserati revised the Tipo 107, adding the twin headlights already used on the U. S. model. A leaf-sprung solid axle took place of the previous De Dion tube, the interior was completely redesigned, including the dashboard which now had a full width wood-trimmed fascia. In 1968 alongside the 4. 1-litre a 4. 7-litre version became available, top speed increased to a claimed 255 km/h, making the Quattroporte 4700 the fastest four-door saloon in the world at the time. Around 500 of the series were made, for a total of 776 Tipo 107 Quattroportes. The first generation Quattroporte had a unibody structure, complemented by a front subframe. Front suspension was independent, with springs and hydraulic dampers. On both axles there were anti-roll bars, brakes were solid Girling discs all around. A limited slip differential was optional, the long lived quad cam, all-aluminium Maserati V8 engine made its début on the Quattroporte. In 1971, Karim Aga Khan ordered another special on the Maserati Indy platform, rory Brown was the chief engineer.
It received the 4. 9-litre V8 engine, producing 300 PS, Carrozzeria Frua designed the car, the prototype of which was displayed in Paris 1971 and Geneva 1972. The car was ready, even receiving its own chassis code
Compared to OHV pushrod systems with the same number of valves, the reciprocating components of the OHC system are fewer and have a lower overall mass. Though the system drives the camshafts may be more complex, most engine manufacturers accept that added complexity as a trade-off for better engine performance. The fundamental reason for the OHC valvetrain is that it offers an increase in the ability to exchange induction. Another performance advantage is gained as a result of the better optimised port configurations made possible with overhead camshaft designs, with no intrusive pushrods, the overhead camshaft cylinder head design can use straighter ports of more advantageous cross-section and length. The OHC design allows for higher speeds than comparable cam-in-block designs. The higher engine speeds thus allowed increases power output for a given torque output, in earlier OHC systems, including inter-war Morrises and Wolseleys, oil leaks in the lubrication systems were an issue. Single overhead camshaft is a design in which one camshaft is placed within the cylinder head, in the SOHC design, the camshaft operates the valves directly, traditionally via a bucket tappet, or via an intermediary rocker arm. SOHC cylinder heads are less expensive to manufacture than double overhead camshaft cylinder heads.
Timing belt replacement can be easier since there are fewer camshaft drive sprockets that need to be aligned during the replacement procedure, SOHC designs offer reduced complexity compared to overhead valve designs — when used for multivalve cylinder heads, in which each cylinder has more than two valves. Exhaust and inlet manifolds were both on the side of the engine block. This did, offer excellent access to the spark plugs, in the early 1980s, Toyota and Volkswagen Group used a directly actuated, SOHC parallel valve configuration with two valves for each cylinder. The Toyota system used hydraulic tappets, the Volkswagen system used bucket tappets with shims for valve clearance adjustment. Honda used a similar system in their motorcycles, using the term Unicam for the concept. This system uses one camshaft for each bank of cylinder heads, with the cams operating directly onto the valve and indirectly, through a short rocker arm. This allows a compact, light valvetrain to operate valves in a combustion chamber.
The Unicam valve train was first used in single cylinder dirt bikes, a dual overhead camshaft valvetrain layout is characterised by two camshafts located within the cylinder head, one operating the intake valves and the other one operating the exhaust valves. This design reduces valvetrain inertia more than is the case with a SOHC engine, a DOHC design permits a wider angle between intake and exhaust valves than do SOHC engines. This can allow for a less restricted airflow at higher engine speeds, DOHC with a multivalve design allows for the optimum placement of the spark plug which, in turn, improves combustion efficiency
A V6 engine is a V engine with six cylinders mounted on the crankshaft in two banks of three cylinders, usually set at either a 60 or 90 degree angle to each other. The V6 is one of the most compact engine configurations, usually ranging from 2.0 L to 4.3 L displacement, shorter than the inline 4, because of its short length, the V6 fits well in the widely used transverse engine front-wheel drive layout. The V6 engine has become widely adopted for medium-sized cars, often as an engine where an inline 4 is standard. Modern V6 engines commonly range in displacement from 2.0 to 4.3 L, though larger and smaller examples have been produced, such as the 1991 Mazda MX3, some of the first V6-powered automobiles were built in 1905 by Marmon. This firm became something of a V-engine specialist, beginning with V2 engines, V4s, V6s, V8s, and, in the 1930s, Marmon was one of the few automakers of the world to offer a V16-powered automobile. From 1908 to 1913 the Deutz Gasmotoren Fabrik produced benzene electric train sets used a V6 as generator engine.
Another V6-powered car was designed in 1918 by Leo Goosen for Buick Chief Engineer Walter L. Marr, only one prototype Buick V6 car was built in 1918, it was long used by the Marr family. The first series-production V6 was introduced by Lancia in 1950 with the Lancia Aurelia model, Lancia sought a smoother and more powerful engine that would fit into an existing narrow engine bay. A Lancia engineer, Francesco De Virgilio, began analyzing the vibration of alternative V-angles for a V6 engine in 1943 and he found that a V6 with its cylinders positioned at a 60° V-angle could be made uniquely smooth-running in comparison with other possible V-angles. There was resistance to his conclusion, because the V6 was a virtually unknown engine type in the 1950s and his design featured four main bearings and six crankpins, resulting in evenly spaced firing intervals and low vibrations. Other manufacturers took note and soon other V6 engines were designed, the use of the sweet spot of 60 degrees V-angle maximized power while minimizing vibration and exterior dimensions of the engine.
In short, GMC introduced a compact V6 design at a time when the engine was considered the pinnacle of 6-cylinder design. To save design time and expense, it was much like a V8 that had two cylinders chopped off. This uneven firing caused harmonic vibrations in the train that were perceived as a rough-running engine by the buyers. GM sold the tooling to Kaiser-Jeep in 1967, later, as a result of the 1973 oil crisis. In 1977, Buick introduced a split pin crankshaft to implement a version of this engine in which cylinders fired consistently every 120°. The V6 does not have the inherent freedom from vibration that the inline-six and flat-six have, counterweights on the crankshaft and a counter rotating balance shaft are required to compensate for the first order rocking motions. This causes an end-to-end rocking motion at crankshaft speed in a straight-three engine and this results in an engine which is short and relatively smooth, but too wide for most engine compartments
Ferrari 212 Inter
The Ferrari 212 Inter replaced Ferraris successful 166 and 195 Inter grand tourers in 1951. Unveiled at the Brussels Motor Show that year, the 212 was an evolution of the 166 — a sports car for the road that could win international races, the chassis was similar to the 125 with a suspension featuring double wishbones in front and live axle in back. Coachbuilders included Carrozzeria Touring, Ghia-Aigle, Stabilimenti Farina, the latter was an important move for the company, as Farina was already well-known and adding his styling skills would be a tremendous boost for Maranello. However, Pinin Farina was as prideful as Enzo Ferrari, a mutual meeting halfway between Maranello and Turin was the negotiated solution. First Ferrari to be bodied by Pinin Farina was 212 Inter Cabriolet, the Inters 2,600 mm wheelbase was 4 longer than the 2,500 mm Exports. The cars shared a larger, bored-out 2.6 L version of Ferraris Colombo V12 engine, output was 150 hp for the single Weber 36DCF carburetor Inter,165 hp for the triple Weber Export.
Improved cylinder heads raised power 5 hp in 1952, the British magazine Autocar got hold of what they described as the first production model Ferrari 212 in 1950, which outperformed any car that they had previously tested. It recorded a top speed of over 116 mph and acceleration times of 0 to 60 mph of 10.5 seconds and 100 mph in 22, the test appears to have been the Autocar teams first encounter with a five speed gear box. A single 212 Inter, chassis no, 0223EL2, was fitted with the available 225 or 2.7 L Colombo V12, creating a unique model that would be properly referred to as a 225 Inter. This one-off model was given a Giovanni Michelotti penned berlinetta body by Vignale
Maserati is an Italian luxury vehicle manufacturer established on 1 December 1914, in Bologna. The companys headquarters are now in Modena, and its emblem is a trident and it has been owned by the Italian-American car giant Fiat Chrysler Automobiles and FCAs Italian predecessor Fiat S. p. A. since 1993. In May 2014, due to plans and product launches. This caused them to production of the Quattroporte and Ghibli models. Maserati is placing a production output cap at 75,000 vehicles globally, the Maserati brothers, Bindo, Carlo and Ernesto were all involved with automobiles from the beginning of the 20th century. Alfieri and Ernesto built 2-litre Grand Prix cars for Diatto, in 1926, Diatto suspended the production of race cars, leading to the creation of the first Maserati and the founding of the Maserati marque. One of the first Maseratis, driven by Alfieri, won the 1926 Targa Florio, Maserati began making race cars with 4,6,8 and 16 cylinders. The trident logo of the Maserati car company is based on the Fountain of Neptune in Bolognas Piazza Maggiore, in 1920, one of the Maserati brothers, artist Mario, used this symbol in the logo at the suggestion of family friend Marquis Diego de Sterlich.
Alfieri Maserati died in 1932, but three brothers, Bindo and Ettore, kept the firm going, building cars that won races. The brothers continued in engineering roles with the company, Racing successes continued, even against the giants of German racing, Auto Union and Mercedes. In back-to-back wins in 1939 and 1940, a Maserati 8CTF won the Indianapolis 500, the war intervened, Maserati abandoned car making to produce components for the Italian war effort. During this time, Maserati worked in fierce competition to construct a V16 town car for Benito Mussolini before Ferry Porsche of Volkswagen built one for Adolf Hitler and this failed, and the plans were scrapped. Once peace was restored, Maserati returned to making cars, the Maserati A6 series did well in the racing scene. Key people joined the Maserati team, alberto Massimino, an old Fiat engineer, with both Alfa Romeo and Ferrari experiences oversaw the design of all racing models for the next ten years. With him joined engineers Giulio Alfieri, Vittorio Bellentani, and Gioacchino Colombo, the focus was on the best engines and chassis to succeed in car racing.
These new projects saw the last contributions of the Maserati brothers and this new team at Maserati worked on several projects, the 4CLT, the A6 series, the 8CLT, pivotally for the future success of the company, the A6GCS. Other racing projects in the 1950s were the 200S, 300S, 350S, Maserati retired from factory racing participation because of the Guidizzolo tragedy during the 1957 Mille Miglia, though they continued to build cars for privateers. Maserati became more and more focused on building road-going grand tourers, the 1957 Maserati 3500 GT marked a turning point in the marques history, as its first ground-up grand tourer design and first series produced car