CH. 27 Turbochargers QUIZ

What is the typical volumetric efficiency range for naturally aspirated engines?

• 50-60%

• 60-70%

• 75-80%

• 80-90%

What is the effect of altitude compensation on engines?

• Increases engine noise

• Normalizes engine performance

• Decreases fuel efficiency

• Reduces engine power

What happens to naturally aspirated engines as altitude increases?

• They gain power.

• They lose 3% of power for every 1000 ft. of altitude increase.

• They remain unaffected.

• They lose 10% of power for every 1000 ft. of altitude increase.

What is one of the effects of altitude on turbocharger effectiveness?

• It decreases due to lower pressure.

• It remains the same.

• It increases because of greater pressure differential at turbine wheel.

• It decreases because of higher temperatures.

What is turbo lag?

• The delay between the point when the driver pushes the accelerator and when the engine responds with more power.

• The time it takes for the engine to cool down.

• The time it takes for the fuel to ignite.

• The delay in the exhaust gas leaving the cylinder.

What happens to the pressure past the turbine housing when the exhaust drives the turbine?

• It increases significantly.

• It remains constant.

• It drops because of little restriction.

• It increases because of high restriction.

What is the purpose of the bypass valve in wastegate turbochargers?

• To increase the engine's power density.

• To open and waste some exhaust gas during high-boost conditions.

• To reduce the size of the turbine housing.

• To control the spring-loaded piston.

What are VGTs capable of changing?

• A. Engine temperature

• B. Boost pressure independent of engine speed and load

• C. Fuel efficiency

• D. Exhaust emissions

What is one characteristic of VGTs?

• A. They have slow reactions

• B. They can create back-pressure for use with EGR engines

• C. They are only used in gasoline engines

• D. They cannot be electronically controlled

Where are parallel turbochargers usually found?

• A. In-line engines

• B. V-type engines

• C. Rotary engines

• D. Boxer engines