Chapter 16I;ngine Size and

PerformanceMeasurements

Name: _______________________ Date:

Instructor: Score: Textbook pages 216-223

Objective: After studying this chapter, you will be able to explain the most important measurements of engine size andperformance.

Engine Size Measurement

1. How is engine size determined? _

2. Define cylinder bore. _

3. How is cylinder bore measured? _

4. Cylinder bores vary in size from __ to __ . 4. _

5. Define piston stroke. _

6. The amount of offset built into the __ controls the piston stroke. 6. _

7. If an engine's specs for bore and stroke are given as 4.00" x 3.00", what does it mean?

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74 Modern Automotive Technology Workbook

8. Generally, a larger __ and a longer stroke make an engine morepowerful.

9. Piston displacement is the volume the piston displaces as it travels from 9. _to

8. _

10. A large cylinder diameter and large piston stroke produce a large piston 10. _

11. If an engine has a bore of 3" and a stroke of 4", what is its piston 11. _displacement?

12. Engine displacement is the volume displaced by all the __ in an engine. 12. _

13. If one piston displaces 30 cu. in. and the engine has four cylinders, what is 13. _the engine's displacement?

14. Engine displacement is usually matched to the __ of the car. 14. _

15. Identify the bore and stroke areas of measurement indicated below.

c

(A) _

(B) _

(C) _(D) _(E) _

(F) _

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F E

Force, Work, and Power16. DefineJorce. _

17. If you use a hoist to lift a 600 lb. engine 5' in the air, how much work has 17. _been done?

18. Definepower. _

19. The metric unit for power is the __ .

20. How much power is needed for an engine to move a 4000 lb. car 2000' inone minute?

19. _

20. _

Name _ Chapter 16 Engine Size and PerformanceMeasurements

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21. Define compression ratio. _

22. In a compression ignition engine, the BDC cylinder volume is __ times 22. _as large as the TDC cylinder volume.

(A) four(B) twelve(C) seventeen(D) fifty

23. Define compression pressure. _

24. Compression pressure is normally measured in __ .(A) Kilopascals(B) pounds per square inch(C) newtons(D) Both A and B.

24. _

25. What is the normal compression pressure for a modem automotive 25. _gasoline engine?

26. A(n) __ is used to measure engine compression pressure. 26. _

27. What are possible indications that an engine's compression pressure is low? _

28. Define engine torque. _

29. Engine torque specifications are given in a(n) __ . 29. _

Horsepower

30. What is engine horsepower? _

31. About how much horsepower would be needed for a small engine to lift 31. _10001b. a distance of 500' in one minute?

32. __ measures the usable power at the engine crankshaft. 32. _

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33. A(n) __ is used to measure the brake horsepower of modem car engines. 33. _

34. A(n) __ measures the horsepower delivered to the drive wheels.

35. Define indicated horsepower. _

34. _

36. Explain frictional horsepower. _

37. __ horsepower is the maximum power developed when an engine is 37. _loaded by all accessories.

38. __ horsepower is the engine power available with only basic accessories 38. _installed.

39. __ horsepower is simply a general rating of engine size. 39. _

Engine Efficiency

40. What is meant by engine efficiency? _

41. Modem piston engines are only about __ percent efficient. 41. _

42. __ is the ratio of air drawn into the cylinder and the maximum possible 42. _amount of air that could enter the cylinder.

43. Define mechanical efficiency. _

44. Normally, __ of an engine's power is lost to friction.(A) 10%-15%(B) 20%-30%(C) 35%-40%(D) 40%-55%

44. _

45. Thermal efficiency measures the amount of __ converted into crank- 45. _shaft rotation.

46. A gallon of gasoline has about __ Btu (British thermal units) of heat 46. _energy.