Hankering for a change of venue? Hungry for a diet of fine Italian cuisine? Like to work for one of the world’s most prestigious carmakers? You’re in luck because Ferrari is recruiting. But before throwing your graduation cap into this big-time ring, bone up with this quiz, which we understand is given to prospective hires by the Maranello-based automaker. And no fair peeking prematurely at the answers.
Comment on one of the below:
A) What are the advantages and disadvantages of gasoline direct injection versus port fuel injection?
B) What are the advantages and disadvantages of a dry sump versus wet sump lubrication system?
Select the one correct answer for the following:
1. What oil pump architecture is most common?
a. rotary
b. centrifugal
c. vane
d. membrane
2. Where are blow-by gases directed?
a. intake manifold
b. exhaust manifold
c. atmosphere
d. crankcase
3. What is a typical mean piston speed for a racing engine?
a. 10 meters/second
b. 20 m/s
c. 40 m/s
d. no limit
4. What function does a secondary air system serve?
a. cool the exhaust stream
b. regulate the lambda sensor
c. increase the catalyst light-off time
d. decrease the catalyst light-off time
5. Which of the following spins at the highest rpm?
a. alternator
b. crankshaft
c. power steering pump
d. air-conditioning compressor
6. Which treatment or coating is used to reduce friction in critical engine parts?
a. metal smoothing
b. hardening
c. diamond-like carbon
d. anodizing
7. What affect does increasing air tumble have on combustion?
a. decreases flame dissipation in a combustion kernel
b. increases flame dissipation in a combustion kernel
c. decreases combustion chamber temperature
d. increases combustion chamber temperature
8. Peak power in a gasoline engine occurs near what lambda value?
a. 0.8
b. 0.9
c. 1.0
d. 1.1
9. Which of the following would increase the likelihood of detonation?
a. advanced spark timing
b. additional EGR
c. reduced compression ratio
d. increased tumble and swirl
10. Which of the following light-duty vehicle exhaust constituents are not regulated by the Environmental Protection Agency?
a. carbon monoxide
b. carbon dioxide
c. nitrous oxides
d. formaldehyde
ANSWER KEY
A) The cooling effect of squirting fuel directly into the combustion chamber allows use of a higher compression ratio. In addition, no fuel droplets are left behind in the intake port. On the debit side, up to 400 times higher fuel pressure is required with direct injection adding to cost and parasitic power losses. Also, carbon build-up on the intake valves can be an issue with direct injection (because no liquid fuel is present to cleanse the valves’ back sides). Tailpipe soot is also often reported in some direct-injection cars.
B) Dry-sump lubrication is significantly more dependable during aggressive acceleration, braking, and cornering events. It also facilitates mounting the engine lower in the vehicle without loss of ground clearance. The debit side is that oil must be scavenged from the crankcase and pumped to a remote reservoir.
1–a (most commonly called a gerotor pump), 2–d (in race engines, these gases are vented to atmosphere; in road cars they are routed to the intake manifold for combustion), 3–c, 4–d, 5–a, 6–c, 7–a, 8–b, 9–a, 10–d
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