Real-Life Math
One of your regular clients, Mrs. Matthews, has been bringing her
baby blue 1967 Mustang into your shop for years. She won't let anyone
but you work on her prized car, which she has named Clive.
Today, Mrs.
Matthews comes into the shop a little concerned. Clive, she tells you, has
been stalling and chugging. And she's pretty sure Clive's gas mileage
isn't what it used to be. You reassure Mrs. Matthews. She always had
faith in your abilities and talents, and you don't intend to let her
down now.
What she has said helps you determine that there's something
wrong with the carburetor. The carburetor mixes the air and the gas into the
proper ratio for combustion. If the mixture is too rich in fuel, then the
gas consumption is high and causes rough idling.
It doesn't take
you long to figure out that the carburetor is toast and will have to be replaced.
You put in a new carburetor, but you have to ensure that Clive's engine
has a sufficient amount of air entering the cylinders. The trick is to determine
the airflow requirements for that size engine.
Note: rpm = revolutions
per minute
The formula for airflow is:
Maximum
airflow = (engine displacement / 2) x (rpm / 1,728) x volumetric efficiency
Assume
the following:
- Airflow has the units of cubic feet per minute
- Volumetric efficiency is 100 percent (use the percent efficiency divided
by 100 -- the percentage written as a decimal)
- Clive has an engine displacement of 300 cubic inches and a maximum engine
speed of 3,600 rpm
Using this information, calculate the airflow for this engine.