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.?
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
(the kind in a car) 1. The first stroke is when the cylinder moves down
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)
pushed upwards pressurizing the air fuel mixture, when the piston just
to the maximum height the spark from the spark plug ignites the mixture
causing the (third stroke) piston to be driven downwards. The fourth
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
inlet valve opens.
As for the number--like v4 or v8 that designates the design and how
cylinders and pistons it has. The v8 engine is arranged so four pistons
on each side. All eight pistons share the rotating main shaft, so the
bank of cylinders are arranged (usually) at about a 60 degree angle to
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
another, or the angle is 180 degrees between the two banks of
As for the twin valve, that is simply how many valves each cylinder
From the example above-the air and exhaust valves-this just represents
many it has per cylinder. A twin valve usually means that two valves of
same size open during the air intake. Most cars only have a single
valve although some have multiple valves. The Lamborghini engine is a
with 48 valves so 48 divided by 12 equals 4 valves per cylinder.
Hope this helps
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Update: June 2012