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Name: Siddharth
Status: Student
Age: 19
Location: N/A
Country: N/A
Date: N/A


Question:
What is the role of a cylinder in a car and how do we diffrentiate between them ..(like v4,v8etc.) also what dowe mean my 4 cylinder twin valve etc.?



Replies:
A cylinder is where all the work is completed. The cylinder houses the piston, and the piston goes up and down in the cylinder. For a four stroke (the kind in a car) 1. The first stroke is when the cylinder moves down the air inlet valve opens and allows air and fuel to enter the cylinder. 2.

Then the piston (which is also connected to the rotating main shaft) gets pushed upwards pressurizing the air fuel mixture, when the piston just gets to the maximum height the spark from the spark plug ignites the mixture causing the (third stroke) piston to be driven downwards. The fourth stroke is when the piston rises once again while the exhaust valve opens and releases the exhaust, on the downstroke the cycle starts over and the air inlet valve opens.

As for the number--like v4 or v8 that designates the design and how many cylinders and pistons it has. The v8 engine is arranged so four pistons are on each side. All eight pistons share the rotating main shaft, so the other bank of cylinders are arranged (usually) at about a 60 degree angle to each other thus forming a V. Other configurations may be straight or horizontally opposed (flat). A straight simply means that all eight cylinders are inline with one another. A flat is the cylinders oppose one another, or the angle is 180 degrees between the two banks of cylinders.

As for the twin valve, that is simply how many valves each cylinder has. From the example above-the air and exhaust valves-this just represents how many it has per cylinder. A twin valve usually means that two valves of the same size open during the air intake. Most cars only have a single exhaust valve although some have multiple valves. The Lamborghini engine is a V12 with 48 valves so 48 divided by 12 equals 4 valves per cylinder.

Hope this helps
Baldwin



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