The V8 car engine can be found under the hood of many powerful cars, such as the Dodge Challenger SRT Demon, Ford F-150, Ford Mustang Shelby GT350, Chevrolet Corvette ZR1 and many more. The V8 engine has a total of eight cylindrical pistons, four on either side of two banks set out in a “V” shape attached to a singular shared crankshaft. This is mainly what the “V” and “8” stand for in the name of the engine. The “V” of the two banks is usually arranged at a 90° angle but can also be found at a steeper angle. From the front it looks like a circle with two points, the banks for the pistons, coming out at an angle and from the side simplistically it is a blocky trapezium shape.
The exact dimensions of the engine depending on the model of car it is in. The length from the rear intake manifold to the water pump pulley can range from 27 inches to 32 inches. The length from the rear mounting surface to the same water pump pulley is between 27 and 34.5 inches. The height from the bottom of the sump to the top of the carburetor is between 27 inches in a Chevy to 34 inches found in some Ford’s. The height from the bottom of the sump to the highest point of the intake manifold can be from 21.5 inches to 27 inches. The width of the entire engine, from the outside of the valve cover to the outside of the other valve cover can usually be 21.5-29.5 inches. The weight of the V8 engine varies greatly from a measly 315 lbs. to 785 lbs. The lightest of which can be found in a Buick and the heaviest in a Mopar.
The V8 engine has a wide array of parts, both moving and stationary, all working in tandem individually yet dependent on one another to keep the rotating.
Piston. The pistons are inside of cylinders. There are right of these on the V8 car engine, four on each of the two banks coming out of the crankshaft. The piston itself is essentially a small cylinder or disk of diameter 67 millimeters a hole through the side of it and an arm with a doing at the end coming out of the bottom which attaches to the crankshaft via the connecting rods. The piston is attached to the crankshaft with a connecting rod bearing. The cylinder in which the piston is gas tight, which is possible because of the piston rings. The gas inside the cylinder expands when heat is provided, expanding the volume pushing the piston. When the heat is removed the volume decreases and hence the piston is pulled back up. This hearty is used to transfer force through the piston to the crankshaft rotating it. The piston is lined with a couple of rings. The top rings are compression rings. These keep the combustion chamber sealed. The bottom ring is called the oil ring, its only purpose is to prevent oil from leaking into the combustion chamber from the crankcase.
Cylinder head.This is made out of aluminum, but there are other engines with cylinder heads made of cast iron, but are less efficient.The cylinder head caps on to the cylinder head forming the combustion chamber. There is something called a head gasket which goes between the cylinder and the cylinder head sealing it in place. The cylinder head forms the top of the combustion chamber with the cylinder as the walls and piston as the floor. This area establishes how the fuel and air mix and in turn how it burns. There are ports/ valves on the cylinder head which air to enter the combustion chamber and exhausted to exit. The larger valve is the intake valve and the smaller valve is the exhaust valve.
Spark plug. The spark plugs present in a V8 are 5/8 inches. There is normally one spark plug per cylinder in a V8 engine, so eight spark plugs, but some V8 engines called Hemi V8s use two spark plugs per cylinder, hence sixteen in total. The function of the spark plug is to ignore the mixture of air and fuel in the combustion chamber. Electricity flows through the spark plug and at the tip it jumps a small gap which creates a spark. This ignites the mixture present in the combustion chamber. It also removes extra heat energy from the combustion chamber to keep it cool until it needs to be ignited. The spark plug is at the top of the combustion chamber in the cylinder head, between the intake and exhaust valves.
Distributor. The ignition system distributor is a key component of the functionality of the engine and the engine is highly dependent on it. It receives electricity from the ignition coil, sending high volts of electricity pulsing to the intended spark plug. The distributor contains a rotor inside it’s cap which is connected to the said ignition coil. The rotor rotates past contact points, one for each of the cylinders/spark plugs. Whenever the rotor passes one of these contacts the high voltage travels from the rotor to the contact point. This is the pulse of electricity which ignites the spark plugs, causing the combustion in each of the combustion chambers
Engine Block. The engine block is basically a large cast iron or aluminum alloy mold. It job is to contain and hold in place a wide array of parts essential to the engine, those parts being the crankcase, it’s gaskets and valves, the eight cylinders and the pistons inside, where the combustion chamber is. The oil pan is also attached to the bottom of the engine block Not only does it just hold all these parts but also provides passages for coolant and oil, sealing surfaces/heads and also distribute heat caused by friction to the coolant and the air, much like our own skin.
Push-rod valve train.The purpose of the valve train is to control the functioning of the intake and exhaust valves on the cylinder head, to in turn control the combustion that takes place inside the combustion chamber. Push-rods long thin metal rods which us have what is called a lifter at the bottom. The lobe on the camshaft pushes the push-rod up due to the lifter. This action pushes on the rocker arm which then opens the valve. The rocker arm is essentially a lever which oscillates lifting or releasing either the intake or exhaust valve. This way as the pushrods move up and down the opening and closing of both valves on each combustion chamber are regulated.
Intake manifold.The intake manifold is an array of tubes which distributes air evenly to each of the eight cylinders. This is the air required in the combustion chamber for the reaction to take place. Fuel injectors also inject fuel into the intake manifold which sprays it into the combustion chamber.
Exhaust manifold. The exhaust manifold is almost the opposite of the intake manifold. It is an array of pipes which act as funnel and collects all the exhaust from the combustion which takes place in the combustion chamber and releases them through the exhaust system when they are completely used up.
Camshaft. A camshaft is a long steel rod which extends through the length of the engine. The camshaft has egg-shaped discs that are not centered on the rod called cams. The pushrods of the valve train for the engine are in contact with these cams. This is so that when the camshaft rotates the push rod is pushed up and down due to the cams not being centered. There are several of these radial cams along the length of the camshaft as there are several valves. The radial cams are all off entered in a pattern, not all on one side, so that the intake valve and exhaust valve are open at opposite times of each rotation of the camshaft. This allows the Camshaft to control the RPM of the car and is also considered the brain of the engine. The cam shaft achieves its rotational movement by being connected to the crankshaft by a timing chain. There are also two camshafts present for the V8 engine, one for each of the banks of pistons, where’s as most other engines only require one.
Timing chain. The timing chain of a V8 is similar to the chain of a bicycle and is comprises of metal links. The links give the chain the ability to hook onto gears and wheels Its purpose is to transfer the movement of the crankshaft to rotate the camshaft, which in turn pushes the push-rods up and down controlling the opening and closing of the intake and exhaust valves. It keeps all these parts in perfect sync so that there is no clashing of parts or movement. Most V8s also have single roller timing chains, rather than double or triple, because single rollers are optimal for high performance engines.
Camshaft pulley. The camshaft pulley is one of the components of the timing system. It is basically a gear made out of metal which rotates the camshaft as the timing chain is wrapped around it. The links of the timing chain hook onto the cams of the camshaft pulley rotating it. This is another component upon which the RPM of the vehicle highly depends on.
Connecting rods. The connecting rod connects the piston to the crankshaft. Therefore, on a V8 engine there are 8 connecting rods, one for each of the pistons. This way the movement of the pistons is used to move rotate crankshaft. The connecting rod looks more or less like a small arm with two rings on either end with bearings, one small one large. The small ring goes inside the piston while the larger ring goes around the crankshaft.
Crankshaft.The crankshaft, in simple terms, is used to transform the up and down movement of the pistons into rotation. It fits along the length of the engine block near the bottom. The Crankshaft is considered the backbone of the Engine. The area where the bearing of the connecting rods holds the crankshaft is known as the journals, of which there are two types, crank journals, attaches to the centerline of the crank, and rod journals which attach to the connecting rods. Much like the camshaft, along the length of the crankshaft there are lobes, balancing lobes. These act as counterweights to cancel out the force of the pistons by exerting force in the opposite direction. When the piston pushes down the lobe is pushing up and vice versa. This is to prevent damage to the crankshaft from force of the pistons, the rotation of the wheels and the friction with the surface. At the front of the engine the crankshaft is connected to the camshaft via the timing chain. This transfers the rotational movement of the crankshaft, by the linear movement of the pistons, to the camshaft of, rotating it. At the back end of the engine the crankshaft attaches the drivetrain. At both of these ends of the crankshaft there are O-rings, which prevent oil from leaking out of the engine.
Crankcase.The crankcase is just below the engine block. This protects the crankshaft and the connecting rods from everything outside. It is also the biggest part of the Engine and basically holds everything together. That’s why it is considered the body of the engine.
Water pump.The water pump of an engine simply pump coolant throughout the engine to regulate the temperature inside the engine to prevent overheating of certain parts. This works much like a heart in a human body. It also has a gasket which keeps the surface of the engine block and the water pump sealed. This prevents leakage of the coolant.
Oil pan.The oil pan is a reservoir of oil attached to the bottom of the engine. This is either made out of steel or aluminum and is able to hold around 7.9 quarts of oil. This oil is pumped from the oil pan and travels throughout the engine and is used as lubricant and to clean the moving parts in the engine and drips back down to the pan.
Oil filter. This component does pretty much what its name suggests. It filters and removes dirt and impurities from the engine oil. This is important because the oil goes on most of the moving parts, so these pollutants can seriously damage integral parts of the engine.
References
Brett, “Gearhead 101: Understanding How Your Car’s Engine Works”, The Art of Manliness, October 15, 2015, https://www.artofmanliness.com/articles/how-a-cars-engine-works/
V8 Engine Block Diagram Tips Electrical Wiring. (2019). [Photograph]. Fuse Wiring. https://hestiahelper.blogspot.com/2018/08/simple-v8-engine-diagram.html#
“AutoEducation.com.” The Valvetrain and How It Works., https://www.autoeducation.com/rm_preview/valve_train.htm#:~:text=The%20valve%20train%20refers%20to,the%20intake%20and%20exhaust%20valves.&text=Other%20designs%20locate%20the%20camshaft,timing%20chain%20or%20direct%20gear.
Muir, Alex. “Cylinder Heads – the Complete Guide.” How a Car Works, How a Car Works, 2011, www.howacarworks.com/cylinder-head.
Szymkowski, Sean. “How Does a V-8 Engine Work?” Motor Authority, 20 Aug. 2018, www.motorauthority.com/news/1118186_how-does-a-v-8-engine-work.
Reflection.
My technical description was on the V8 engine. The genre is a technical writing. Being a technical description, the essay did not require engagements with the audience other than plain explanations. The goal of the writing was to list and explain the function of the various part of the V8 engine, as well as how they all work together to accomplish what. The tome I used was a formal informative one. I thought this would be the best, most appropriate way to conduct my information to make it easy for the reader to understand.
There was more than one course learning outcomes that I was able to achieve in the process of writing this technical description. From scouting multiple sources and reading published work I was able to strengthen my source practices leading me to also enhance strategies for reading, drafting, revising, editing, and self-assessment and engage in genre analysis and multimodal composing to explore effective writing across disciplinary contexts and beyond.
