functions of the car Flashcards
Radiator
The engine block is hot from internal combustión and friction. The motor oil helps a ton but its not enough.
Water and antifreeze are pumped into chambers to absorb excess heat and draw it away from vital areas.
The fluid returns to the radiator by a hose. The radiators large and has many coils. This is purposeful so that the surface area can cool down the fluid by a fan y the outside air. Its important to have enough coolant.
differential
- Exists so that when you turn wheels move at the same speed and can turn independently of each other
- moves energy from the engine to the wheels and to the drive train.
- low center drive: meaning the drive train is at the bottom of the differential and is under the car.
differential
connected to the differential
Horsepower
- how much work you can get done in a certain time
- a measure of power. shows how much work the engine can do
torque
- twisting force. how hard you can twist something without regard to time.
- ft/pounds
- with turbo, the torque width stays high for a long amoung of time.
- when rpms get really high, torque starts to drop because the engine can’t breath sufficiently.
horsepower vs torque
torque is twist
rpm
revolutions per minute
largely a product of rpm x torque
main components of an engine
block, cylinders, pistons, spark plugs, fuel injectors, intake and exhaust valves, timing chain/belt, crankshaft, connecting rods, camshaft.
how is power made in engine
4 strokes
- down. intake valve opens and fuel and air move in
- up. compression of air and fuel mixture
- down because a spark ignites the compressed gas.
- exhaust stroke up. the exhaust valve opens and the burn air is shot up and out to leave by exhaust pipe.
bore
how wide the cylinder is
compression ratio
ration between when the piston is at the bottom of the cylinder and when it is at the top.
higher compression ration requires more fuel but give more power
displacement
how the internal size of the engine is described.
cylinder bore x stroke length x number of cylinders and is expressed in liters.
valves, how many and how do they open and close
most high performance vehicles have two intake and two outtake valves per piston.
they open by camshaft that has push valves.
dohc vs sohc
dohc- one camshaft for the intake valves and another for the outtake.
sohc- single overhead camshaft that takes care of the opening and closing.
why the v?
any car with more than 4 cylinders has a v
what is ACIS
it helps pump more air into the engine so it can breath better
VVTI
computerized system that optimizes breathing and valve opening and closing timing, the vvti adjusts based on speed to provide maxium benefit of the engine at different speeds.
radiator purpose simply
help cool down the engine
why the coils and large surface area of the radiator?
the surface area allows for greater cooling capacity
crankshaft, how does it turn?
4 stroke engine, the pistons
crankshaft, where does the twisting motion go?
the transmission, specifically the flywheel (which is connected to the clutch)
what is the layshaft in transmission
the part below the transmission with different sized gears to drive the different speeds/power of the engine.
What happens when the clutch is pressed and the pressure plate is moved away from…?
the hydraulics move the clutch against the rotating flywheel. the pressure plate also moves away from the clutch, disengaging the power from the engine.
What happens when the clutch is released
the engine is engaged again.
1st gear torque and speed
high torque, low speed…. high gear is low torque and high speed
where does the spinning motion go after leaving the crankshaft?
transmission and then to differential then to wheels.
transformer
change voltage and current levels
overhead valve
I-head or pushrod
places camshaft just above the crankshaft
adv: compact, less complex
lim… lim rpm, have to take out the engine to mess with the camshaft, noisier
in driving stick, what to do before breaking
clutch
what to always start in driving stick
first gear
