63 + Interview Questions in Valve Timing Technologies in Automotive Engine Design Page 1 InterviewSolution

1.	Which of the mentioned bellow is a disadvantage of a poppet valve?(a) Cold start wear(b) Higher overall valve train efficiency(c) Cylinder deactivation(d) Valve stem scuffingThis question was addressed to me in semester exam.This question is from Variable Valve Timing in portion Valve Timing Technologies of Automotive Engine Design
Answer» Right answer is (d) VALVE stem scuffing The EXPLANATION is: Valve stem scuffing is DUE to GEOMETRICAL irregularities or over-speeding. This can be corrected by bent or slanted valve, which MAY need replacement.

Discussion

2.	How many valves per cylinder are used in Multi air technology?(a) 1(b) 2(c) 3(d) 4This question was posed to me by my school teacher while I was bunking the class.Enquiry is from Variable Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Correct answer is (d) 4 Easy EXPLANATION: In this technology, instead of twin camshafts of four valves per cylinder ENGINE, a SINGLE camshaft opens up all four valves and ELIMINATES engine pumping losses.

Discussion

3.	By which component in a Camless engine, each engine valve is operated individually?(a) ECU(b) Cam(c) Sensor(d) ActuatorI got this question by my school teacher while I was bunking the class.This key question is from Variable Valve Timing topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» Right ANSWER is (d) Actuator Easiest EXPLANATION: In a Camless ENGINE, each engine VALVE is operated individually by an actuator. There is no camshaft. So cylinder DEACTIVATION is possible.

Discussion

4.	What was the Fiat’s new air management technology in 2009 known as?(a) I-VTEC(b) VVTEC(c) Turbo engine(d) MultiAirThis question was addressed to me in my homework.The above asked question is from Variable Valve Timing in division Valve Timing Technologies of Automotive Engine Design
Answer» RIGHT option is (d) MULTIAIR To explain: Fiat unveiled its new air management technology named ‘MultiAir’ at the 2009 Geneva Motor Show. This is a real TECHNOLOGICAL breakthrough and CLAIMED to be much better than the VVT system.

Discussion

5.	Which valve system varies the valve timing and lift of both intake and exhaust?(a) DOHC(b) SOHC(c) TDCI(d) CRDII got this question in examination.My doubt stems from Variable Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Correct option is (a) DOHC To elaborate: The VTEC used in INDIAN ‘Honda city’ is a SOHC type that VARIES the timing and LIFT of only the intake valves. The DOHC type of VTEC varies VALVE timing and lift of both the intake and exhaust valves. – duplicate of Q8

Discussion

6.	Which type of valve system does the VTEC uses in Indian ‘Honda city’?(a) DOHC(b) SOHC(c) TDCI(d) CRDIThis question was addressed to me by my college professor while I was bunking the class.Origin of the question is Variable Valve Timing topic in section Valve Timing Technologies of Automotive Engine Design
Answer» RIGHT answer is (b) SOHC Explanation: The VTEC used in Indian ‘HONDA city’ is a SOHC type that varies the TIMING and LIFT of only the intake valves. The DOHC type of VTEC varies valve timing and lift of both the intake and exhaust valves.

Discussion

7.	What results in the use of a high degree of overlap inat lower engine speed?(a) Loss of torque(b) Gain of performance(c) loss of torque and performance(d) Gain of torque and performanceI have been asked this question during an interview for a job.The doubt is from Variable Valve Timing topic in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Right ANSWER is (C) loss of torque and performance The best I can explain: The use of a high DEGREE of valve overlap results in a loss of torque and performance at lower engine speeds. Moreover, the engine idling is also unstable-the engine hunts and misses, on STALL.

Discussion

8.	What is the value of the valve overlap, for a smooth idle and healthy low rpm torque?(a) 0(b) 40°-75°(c) 1(d) 80°-150°This question was posed to me during an internship interview.Asked question is from Variable Valve Timing topic in section Valve Timing Technologies of Automotive Engine Design
Answer» Right answer is (a) 0 For explanation: For a smooth idle and HEALTHY LOW rpm torque we NEED to have zero VALVE overlap between the inlet and exhaust valve. Hence, 0 is the right answer.

Discussion

9.	What does VTEC stands for?(a) Valve timing and lift electronic control system(b) Variable valve timing and lift electronic system(c) Variable timing electronic system(d) Variable valve timing and lift electronic control systemThis question was posed to me in class test.The above asked question is from Variable Valve Timing topic in chapter Valve Timing Technologies of Automotive Engine Design
Answer» The correct option is (d) Variable VALVE timing and LIFT electronic control system Explanation: VTEC stands for variable valve timing and lift electronic control system. This creates a LARGE amount of OVERLAP between the inlet and the exhaust valves, is beneficial at high speeds.

Discussion

10.	Which system reduces the pumping losses due to conventional throttle?(a) Profile switching system(b) Phase changing system(c) Variable event-timing system(d) Variable lift systemThis question was addressed to me in an online interview.I'm obligated to ask this question of Variable Valve Timing topic in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Correct OPTION is (d) Variable lift system Easy EXPLANATION: Variable lift system has the main advantage of reducing the pumping losses due to conventional THROTTLE. Variable event-timing system can change both the PHASE and duration of the valve events.

Discussion

11.	Which system can change both the phase and duration of the valve event?(a) Profile switching system(b) Phase changing system(c) Variable event-timing system(d) Variable lift systemThis question was posed to me in an interview.The above asked question is from Variable Valve Timing in division Valve Timing Technologies of Automotive Engine Design
Answer» CORRECT choice is (d) Variable lift system To EXPLAIN: Variable event-timing system can change both the phase and duration of the valve EVENTS and can be optimized at different ENGINE speeds and LOAD conditions.

Discussion

12.	Which system can change independently the valve-event timing and valve lift?(a) Profile switching system(b) Phase changing system(c) Variable event-timing system(d) Variable lift systemI got this question during an interview.I would like to ask this question from Variable Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Right CHOICE is (a) PROFILE SWITCHING system The best explanation: The profile switching system can change independently of the VALVE-event timing and valve lift. VARIABLE event-timing system can change both the phase and duration of the valve event.

Discussion

13.	Which technology changes the timing of intake/exhaust valves when the engine is running?(a) CRDI(b) DOHC(c) TDI(d) VVTThis question was posed to me in exam.I want to ask this question from Variable Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design
Answer» The correct answer is (d) VVT To EXPLAIN I would say: VVT is a generic term for an AUTOMOBILE ENGINE technology that allows the timing os the intake/exhaust valves to be changed when the engine is working.

Discussion

14.	Which material is not used for timing gear?(a) Cast iron(b) Steel(c) Nichrome(d) AluminumThis question was posed to me in a national level competition.My question is based upon Valve Train Component Details topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» The correct answer is (c) Nichrome Explanation: Cast iron, steel, and aluminum are all the material used in TIMING gear BASED on their life. Whereas nichrome is a material that is USUALLY found on the HEATING element.

Discussion

15.	Which of the mentioned is the advantage of the toothed belt drive?(a) Silent drive(b) High vibration(c) High heat built up(d) High lubricationI had been asked this question during an internship interview.I need to ask this question from Valve Train Component Details topic in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Right choice is (a) Silent DRIVE Easy explanation: In a flat BELT type, the stress DISTRIBUTION is uneven and there is a slip. To overcome this V-tooths are MADE on it. Silent drive is the advantage of the TOOTHED belt drive.

Discussion

16.	Which component, transmit the torque load from the drive to the drive pulley?(a) Facing(b) Backing plate(c) Molded teeth(d) Load-carrying cordsI have been asked this question during an online interview.Origin of the question is Valve Train Component Details topic in section Valve Timing Technologies of Automotive Engine Design
Answer» CORRECT OPTION is (d) Load-carrying CORDS The BEST I can explain: Load-carrying cords are USED to transmit the torque load from the drive to the drive pulley. These are made of very strong flexible glass-fiber cords.

Discussion

17.	What are bonded to the inside layer of the load-carrying cords?(a) Facing(b) Backing plate(c) Molded teeth(d) Load-carrying cordsThe question was posed to me in exam.My question is based upon Valve Train Component Details in portion Valve Timing Technologies of Automotive Engine Design
Answer» Right choice is (c) Molded teeth The explanation is: MOULDED teeth, which provide grip. NEOPRENE rubber teeth moldings are bonded to the INSIDE layer of the load-carrying cords. SILENT drive is the advantage of the TOOTHED belt drive.

Discussion

18.	In overhead cams, which type of drive is used to drive camshaft?(a) Gear(b) Chain or belt(c) Chain(d) Toothed beltThis question was addressed to me during an interview.This intriguing question originated from Valve Train Component Details topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» Correct ANSWER is (b) Chain or belt For explanation I WOULD SAY: Chain or belt type of drive is used to drive the camshaft. GEARS are space CONSUMING and adds weight to the engine and also is requires lubrication. So, gears are not used.

Discussion

19.	The end wise movement of the camshaft is limited by which component?(a) Key(b) Spigot(c) Thrust plate(d) Shear plateThis question was addressed to me in an online interview.My question is taken from Valve Train Component Details topic in section Valve Timing Technologies of Automotive Engine Design
Answer» Correct answer is (C) THRUST PLATE To explain: The end wise MOVEMENT of the camshaft is limited by the thrust plate. Shear plate is added to bear the load in the weak joint of the welding.

Discussion

20.	What is the range of clearance given between bearing journals and the bores?(a) 0.06 to 0.5cm(b) 0.025 to 1.2mm(c) 0.5 to 1cm(d) 0.05 to 0.125mmI got this question in unit test.This key question is from Valve Train Component Details in portion Valve Timing Technologies of Automotive Engine Design
Answer» Correct ANSWER is (d) 0.05 to 0.125mm Easy EXPLANATION: The clearance GIVEN between BEARING journals and the bores are given in the range of 0.05 to 0.125mm. This ALSO helps in cooling and reduces the wear due to friction.

Discussion

21.	What is the speed of the camshaft rotation?(a) Half the crankshaft speed(b) Double the crankshaft speed(c) Thrice the crankshaft speed(d) Same as crankshaft speedI have been asked this question during an interview for a job.I want to ask this question from Valve Train Component Details in division Valve Timing Technologies of Automotive Engine Design
Answer» The correct CHOICE is (a) Half the CRANKSHAFT speed To explain: The speed of the CAMSHAFT rotation is half the crankshaft speed and in OVERHEAD CAMS,Chain or belt type of drive is used to drive the camshaft.

Discussion

22.	Why is the clearance given between bearing journals and the bores?(a) lubrication and metal expansion(b) Friction(c) For lubrication(d) Thermal expansionThe question was posed to me in an interview for internship.My query is from Valve Train Component Details topic in division Valve Timing Technologies of Automotive Engine Design
Answer» Correct OPTION is (a) LUBRICATION and metal expansion Easy EXPLANATION: The clearance given between BEARING journals and the BORES are given for lubrication and metal expansion in the range of 0.05 to 0.125mm.

Discussion

23.	How many cam lobes are present on the camshaft per cylinder?(a) 6(b) 5(c) 3(d) 2This question was addressed to me during a job interview.This interesting question is from Valve Train Component Details topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» The correct answer is (d) 2 The EXPLANATION is: There will be two cam lobes per cylinder head, ONE is for intake valve and another is for exhaust valve. In MODERN engines, DUAL OVERHEAD cams are also present.

Discussion

24.	In which type of engine Valve train is not present?(a) 4-stroke petrol engine(b) 2-stroke petrol engine(c) 4-stroke diesel engine(d) Boxer engineThis question was posed to me in unit test.Enquiry is from Valve Train Component Details in section Valve Timing Technologies of Automotive Engine Design
Answer» The correct answer is (b) 2-stroke PETROL engine To explain: Valve TRAIN is not present in the 2-stroke petrol engine, but to do the same WORK valves are replaced by ports, and its opening and closing is done by PISTON itself.

Discussion

25.	What is that part of a cam lobe which controls the valve opening called as?(a) Coldspot(b) Hot spot(c) Low spot(d) High spotThe question was asked in my homework.The question is from Valve Train Component Details in division Valve Timing Technologies of Automotive Engine Design
Answer» CORRECT option is (d) High spot Easy explanation: A CAMSHAFT is a shaft with a cam for each intake and exhaust VALVE. Each cam has a high spot called cam lobe which CONTROLS the valve opening.

Discussion

26.	Why there is a small clearance around the stem of the valve?(a) Lubrication(b) Cooling(c) Heating(d) StrengtheningI have been asked this question in an internship interview.Asked question is from Poppet Valves topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» The correct choice is (a) Lubrication Easy EXPLANATION: The small clearance around the stem of the VALVE for lubrication. The valves experience a high temperature since it is in DIRECT contact with the combustion heat. HENCE, lubrication is REQUIRED.

Discussion

27.	What is present around the valve in the engine for the cooling?(a) Radiator(b) Ice pack(c) Water jacket(d) FanI got this question in an interview.Enquiry is from Poppet Valves in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Right choice is (C) Water jacket The best I can explain: Water jackets are PRESENT around the VALVE in the engine for the cooling and there is a small CLEARANCE around the stem of the valve for lubrication.

Discussion

28.	Which material is generally used in valve springs?(a) Carbon steel(b) Chromium-vanadium steel(c) Nickel-chromium steel(d) Both carbon steel or chromium-vanadium steelI have been asked this question during an interview for a job.Query is from Poppet Valves in portion Valve Timing Technologies of Automotive Engine Design
Answer» The correct choice is (d) Both carbon steel or chromium-vanadium steel To explain: The valve SPRINGS are MADE from high-grade spring steel wire, the MATERIALS being generally hard-drawn carbon steel or chromium-vanadium steel.

Discussion

29.	What is the highest temperature experienced by the exhaust valve?(a) 550^oC(b) 400^oC(c) 900^oC(d) 750^oCThis question was posed to me by my college director while I was bunking the class.My doubt is from Poppet Valves in chapter Valve Timing Technologies of Automotive Engine Design
Answer» CORRECT answer is (d) 750^oC The BEST I can explain: The exhaust valve temperature in MODERN engines reach very high valves of the ORDER of 750^oC and sodium is present inside the hollow stem of the valve.

Discussion

30.	What is present inside the hollow stem of the valve?(a) Ethyl-glycol(b) Magnesium(c) Sodium(d) MercuryThis question was posed to me by my school teacher while I was bunking the class.This is a very interesting question from Poppet Valves topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» Right option is (c) SODIUM The best I can explain: The exhaust valve TEMPERATURE in modern ENGINES reach very high. So, sodium is present inside the hollow stem of the valve. These valves are also USED in Heavy engines.

Discussion

31.	To avoid corrosion, the valve is given a coating with what material?(a) Copper(b) Chromium(c) Zinc(d) AluminumThe question was posed to me in an internship interview.This intriguing question comes from Poppet Valves topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» Right option is (d) Aluminum To elaborate: To AVOID corrosion, the valve is GIVEN an aluminum coating. Aluminum oxide formed separates the valve STEM from the cast iron seat to keep the FACE metal sticking.

Discussion

32.	The least coefficient of thermal expansion to avoid excessive thermal stress is experienced by which part of the valve?(a) Head(b) Face(c) Stem(d) MarginThis question was posed to me by my school teacher while I was bunking the class.Enquiry is from Poppet Valves topic in section Valve Timing Technologies of Automotive Engine Design
Answer» Right option is (a) Head The EXPLANATION is: The Least COEFFICIENT of thermal EXPANSION to avoid excessive thermal stress is experienced by the head part of the valve because it experiences the heat from the COMBUSTION directly.

Discussion

33.	Which property of the valve resists the tensile loads and stem wear?(a) Strength(b) Hardness(c) Both strength and hardness(d) ToughnessI got this question during an internship interview.Question is taken from Poppet Valves in section Valve Timing Technologies of Automotive Engine Design
Answer» The correct choice is (C) Both strength and hardness Best explanation: Exhaust VALVE material requires high strength and hardness to resist tensile LOADS and STEM wear. High hot strength and hardness to combat head cupping and wear of SEATS.

Discussion

34.	Circumferential and longitudinal direction of valve experience which stress?(a) Shear stress(b) Principal stress(c) Longitudinal cyclic stress(d) Thermal stressThe question was posed to me by my school principal while I was bunking the class.The query is from Poppet Valves topic in section Valve Timing Technologies of Automotive Engine Design
Answer» Correct choice is (d) Thermal stress The BEST I can explain: Thermal stresses in the circumferential and LONGITUDINAL directions DUE to the large temperature gradient from the CENTRE of the head to its periphery and from the crown to the stem.

Discussion

35.	What is the exhaust valve face angle that is generally kept?(a) 25°(b) 30°(c) 45°(d) 45° or 30°This question was posed to me during an interview.This intriguing question originated from Poppet Valves topic in section Valve Timing Technologies of Automotive Engine Design
Answer» CORRECT ANSWER is (c) 45° The best I can EXPLAIN: The EXHAUST valve face ANGLE is only 45°, as this increases its heat dissipation. In some cases, a further differential angle of about ½ deg to 1 deg is provided between the valve and its seating.

Discussion

36.	What is the inlet valve face angle that is generally kept?(a) 25°(b) 30°(c) 45°(d) 45° or 30°I got this question during an online interview.Question is from Poppet Valves in portion Valve Timing Technologies of Automotive Engine Design
Answer» The CORRECT answer is (d) 45° or 30° The explanation: The inlet valve face angle is generally kept 45° or 30°. A smaller angle provides greater valve opening for a given LIFT, but poor sealing because of the reduced sealing PRESSURE for a given SPRING load.

Discussion

37.	Generally which valve is larger?(a) Exhaust valve(b) Inlet valve(c) Exhaust port(d) Oil portThis question was addressed to me by my college director while I was bunking the class.My question is from Poppet Valves in chapter Valve Timing Technologies of Automotive Engine Design
Answer» CORRECT choice is (b) Inlet valve Best explanation: Generally inlet VALVES are larger than the exhaust valves because the SPEED of incoming air-fuel MIXTURE is LESS than the velocity of exhaust gases which leave under pressure.

Discussion

38.	Which of the mentioned below is the advantage of a poppet valve?(a) Moment of inertia(b) Shape(c) Lightweight(d) Self-centeringThis question was addressed to me during an internship interview.This interesting question is from Poppet Valves topic in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Correct ANSWER is (d) Self-centering For explanation: SIMPLICITY of construction, self-centering, free to ROTATE about the stem, maintenance of sealing efficiency are all the advantages of the poppet VALVE.

Discussion

39.	Which of the mentioned below is not a type of valve?(a) Poppet valve(b) Sleeve valve(c) Rotary valve(d) Non-return valveI got this question in final exam.This key question is from Valve Timing topic in portion Valve Timing Technologies of Automotive Engine Design
Answer» Correct ANSWER is (d) Non-return valve To explain I would say: The Poppet valve, sleeve valve, and rotary valve are all the types of valve used in an internal combustion ENGINE, whereas the Non-return valve is used in the FUEL PUMP.

Discussion

40.	The maximum power output of the engine would generally be increased by increasing what?(a) Throttle position(b) Valve drop(c) Power output(d) Valve peak liftI have been asked this question in examination.Question is from Valve Timing topic in section Valve Timing Technologies of Automotive Engine Design
Answer» Right answer is (d) Valve peak lift To explain: The maximum power output of the engine would generally be INCREASED by increasing the valve peak lift. Higher the valve lift, the more the CHARGE can enter the CYLINDER. Hence, more power is OBTAINED.

Discussion

41.	The maximum valve opening depends directly on what factor?(a) Throttle position(b) Valve drop(c) Power output(d) Valve peak liftI got this question in final exam.Asked question is from Valve Timing topic in chapter Valve Timing Technologies of Automotive Engine Design
Answer» RIGHT choice is (d) Valve peak LIFT The EXPLANATION: The MAXIMUM valve OPENING depends directly on valve peak lift and the maximum power output of the engine would generally be increased by increasing valve peak lift.

Discussion

42.	Practically, Valve overlap at what range at BDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°The question was asked in homework.My doubt is from Valve Timing topic in section Valve Timing Technologies of Automotive Engine Design
Answer» The correct answer is (d) 80°-150° To explain: PRACTICALLY, Valve overlap at20°-60° range at TDC and Valve overlap at 80°-150° range at BDC. THEORETICALLY, the VALVES open and close INSTANTANEOUSLY at the dead centers.

Discussion

43.	Practically, Valve overlap at what range at TDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°I had been asked this question in an online interview.This key question is from Valve Timing in section Valve Timing Technologies of Automotive Engine Design
Answer» The correct CHOICE is (C) 20°-60° For explanation: PRACTICALLY, Valve overlap at20°-60° range at TDC and Valve overlap at80°-150° range at BDC. Valve overlap is the time during which both the inlet and exhaust valves remain OPEN at the same time.

Discussion

44.	What is the event known as when the inlet valve is generally closed after 45° of BDC?(a) Valve bent(b) Valve break(c) Valve lag(d) Valve leadI got this question during an interview for a job.Enquiry is from Valve Timing in portion Valve Timing Technologies of Automotive Engine Design
Answer» Right CHOICE is (c) Valve lag For explanation: The INLET valve is GENERALLY closed after 45° of BDC is known as Valve lag.This valve timing can increase or decrease the POWER of the engine. Hence, precision is REQUIRED in valve timing.

Discussion

45.	Practically, Exhaust valve opens at what range before BDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°The question was posed to me during an interview.My question comes from Valve Timing in division Valve Timing Technologies of Automotive Engine Design
Answer» The CORRECT OPTION is (b) 40°-75° The explanation: The exhaust valve opens before the piston reaches BDC in its POWER stroke. Practically, the inlet valve opens between 10°-30° range before TDC, Exhaust valve opens at 40°-75° range before BDC.

Discussion

46.	Practically, the inlet valve opens between what range before TDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°The question was asked in final exam.This intriguing question originated from Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design
Answer» Correct ANSWER is (a) 10°-30° The explanation is: Practically, the INLET valve opens between 10°-30° RANGE before TDC, Exhaust valve opens at40°-75° range before BDC, Valve OVERLAP at 20°-60° range at TDC and Valve overlap at 80°-150°range at BDC.

Discussion

47.	What is the event known as when the inlet valve is generally opened about 50° TDC is known as?(a) Valve bent(b) Valve break(c) Valve lag(d) Valve leadThis question was addressed to me in an online quiz.My enquiry is from Valve Timing topic in chapter Valve Timing Technologies of Automotive Engine Design
Answer» The CORRECT choice is (d) VALVE lead Explanation: The INLET valve is generally OPENED about 50° TDC is KNOWN as valve lead and the inlet valve is generally closed after 45° of BDC is known as Valve lag.

Discussion

48.	Due to which factor, the valves can’t open instantaneously?(a) Inertia(b) Torsional(c) Momentum(d) Point loadI got this question in my homework.Asked question is from Valve Timing in portion Valve Timing Technologies of Automotive Engine Design
Answer» CORRECT answer is (a) Inertia To explain: In PRACTICE, due to inertia the valves cannot open INSTANTANEOUSLY, and also the air-fuel MIXTURE has its inertia. Consequently, more time has to be allowed for the intake and exhaust process to complete.

Discussion

49.	Theoretically, the exhaust valve should open till the piston reaches which position?(a) Bottom dead centre(b) Side centre position(c) Bottom side position(d) Top dead centreThe question was posed to me in quiz.Enquiry is from Valve Timing in portion Valve Timing Technologies of Automotive Engine Design
Answer» Correct answer is (d) TOP dead centre Best explanation: THEORETICALLY the INLET valve should OPEN at the top dead center position of the piston and the exhaust valve should open till the piston reaches the top dead centre.

Discussion

50.	Theoretically, the inlet valve should close at what position of the piston?(a) Bottom dead centre(b) Side centre position(c) Bottom side position(d) Top dead centreThe question was posed to me by my school principal while I was bunking the class.The origin of the question is Valve Timing in portion Valve Timing Technologies of Automotive Engine Design
Answer» Right choice is (a) Bottom dead centre For explanation: Theoretically the INLET valve should close at Bottom dead centre position of the piston.The EXHAUST valve opens before the piston reaches BDC in its POWER stroke.

Discussion

Explore topic-wise InterviewSolutions in .

How many valves per cylinder are used in Multi air technology?(a) 1(b) 2(c) 3(d) 4This question was posed to me by my school teacher while I was bunking the class.Enquiry is from Variable Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design

What was the Fiat’s new air management technology in 2009 known as?(a) I-VTEC(b) VVTEC(c) Turbo engine(d) MultiAirThis question was addressed to me in my homework.The above asked question is from Variable Valve Timing in division Valve Timing Technologies of Automotive Engine Design

Which valve system varies the valve timing and lift of both intake and exhaust?(a) DOHC(b) SOHC(c) TDCI(d) CRDII got this question in examination.My doubt stems from Variable Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design

What is the value of the valve overlap, for a smooth idle and healthy low rpm torque?(a) 0(b) 40°-75°(c) 1(d) 80°-150°This question was posed to me during an internship interview.Asked question is from Variable Valve Timing topic in section Valve Timing Technologies of Automotive Engine Design

Which technology changes the timing of intake/exhaust valves when the engine is running?(a) CRDI(b) DOHC(c) TDI(d) VVTThis question was posed to me in exam.I want to ask this question from Variable Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design

Which material is not used for timing gear?(a) Cast iron(b) Steel(c) Nichrome(d) AluminumThis question was posed to me in a national level competition.My question is based upon Valve Train Component Details topic in portion Valve Timing Technologies of Automotive Engine Design

What are bonded to the inside layer of the load-carrying cords?(a) Facing(b) Backing plate(c) Molded teeth(d) Load-carrying cordsThe question was posed to me in exam.My question is based upon Valve Train Component Details in portion Valve Timing Technologies of Automotive Engine Design

The end wise movement of the camshaft is limited by which component?(a) Key(b) Spigot(c) Thrust plate(d) Shear plateThis question was addressed to me in an online interview.My question is taken from Valve Train Component Details topic in section Valve Timing Technologies of Automotive Engine Design

What is the range of clearance given between bearing journals and the bores?(a) 0.06 to 0.5cm(b) 0.025 to 1.2mm(c) 0.5 to 1cm(d) 0.05 to 0.125mmI got this question in unit test.This key question is from Valve Train Component Details in portion Valve Timing Technologies of Automotive Engine Design

How many cam lobes are present on the camshaft per cylinder?(a) 6(b) 5(c) 3(d) 2This question was addressed to me during a job interview.This interesting question is from Valve Train Component Details topic in portion Valve Timing Technologies of Automotive Engine Design

In which type of engine Valve train is not present?(a) 4-stroke petrol engine(b) 2-stroke petrol engine(c) 4-stroke diesel engine(d) Boxer engineThis question was posed to me in unit test.Enquiry is from Valve Train Component Details in section Valve Timing Technologies of Automotive Engine Design

What is that part of a cam lobe which controls the valve opening called as?(a) Coldspot(b) Hot spot(c) Low spot(d) High spotThe question was asked in my homework.The question is from Valve Train Component Details in division Valve Timing Technologies of Automotive Engine Design

Why there is a small clearance around the stem of the valve?(a) Lubrication(b) Cooling(c) Heating(d) StrengtheningI have been asked this question in an internship interview.Asked question is from Poppet Valves topic in portion Valve Timing Technologies of Automotive Engine Design

What is present around the valve in the engine for the cooling?(a) Radiator(b) Ice pack(c) Water jacket(d) FanI got this question in an interview.Enquiry is from Poppet Valves in chapter Valve Timing Technologies of Automotive Engine Design

What is the highest temperature experienced by the exhaust valve?(a) 550^oC(b) 400^oC(c) 900^oC(d) 750^oCThis question was posed to me by my college director while I was bunking the class.My doubt is from Poppet Valves in chapter Valve Timing Technologies of Automotive Engine Design

To avoid corrosion, the valve is given a coating with what material?(a) Copper(b) Chromium(c) Zinc(d) AluminumThe question was posed to me in an internship interview.This intriguing question comes from Poppet Valves topic in portion Valve Timing Technologies of Automotive Engine Design

Which property of the valve resists the tensile loads and stem wear?(a) Strength(b) Hardness(c) Both strength and hardness(d) ToughnessI got this question during an internship interview.Question is taken from Poppet Valves in section Valve Timing Technologies of Automotive Engine Design

What is the exhaust valve face angle that is generally kept?(a) 25°(b) 30°(c) 45°(d) 45° or 30°This question was posed to me during an interview.This intriguing question originated from Poppet Valves topic in section Valve Timing Technologies of Automotive Engine Design

What is the inlet valve face angle that is generally kept?(a) 25°(b) 30°(c) 45°(d) 45° or 30°I got this question during an online interview.Question is from Poppet Valves in portion Valve Timing Technologies of Automotive Engine Design

Generally which valve is larger?(a) Exhaust valve(b) Inlet valve(c) Exhaust port(d) Oil portThis question was addressed to me by my college director while I was bunking the class.My question is from Poppet Valves in chapter Valve Timing Technologies of Automotive Engine Design

Which of the mentioned below is not a type of valve?(a) Poppet valve(b) Sleeve valve(c) Rotary valve(d) Non-return valveI got this question in final exam.This key question is from Valve Timing topic in portion Valve Timing Technologies of Automotive Engine Design

The maximum valve opening depends directly on what factor?(a) Throttle position(b) Valve drop(c) Power output(d) Valve peak liftI got this question in final exam.Asked question is from Valve Timing topic in chapter Valve Timing Technologies of Automotive Engine Design

Practically, Valve overlap at what range at BDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°The question was asked in homework.My doubt is from Valve Timing topic in section Valve Timing Technologies of Automotive Engine Design

Practically, Valve overlap at what range at TDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°I had been asked this question in an online interview.This key question is from Valve Timing in section Valve Timing Technologies of Automotive Engine Design

What is the event known as when the inlet valve is generally closed after 45° of BDC?(a) Valve bent(b) Valve break(c) Valve lag(d) Valve leadI got this question during an interview for a job.Enquiry is from Valve Timing in portion Valve Timing Technologies of Automotive Engine Design

Practically, Exhaust valve opens at what range before BDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°The question was posed to me during an interview.My question comes from Valve Timing in division Valve Timing Technologies of Automotive Engine Design

Practically, the inlet valve opens between what range before TDC?(a) 10°-30°(b) 40°-75°(c) 20°-60°(d) 80°-150°The question was asked in final exam.This intriguing question originated from Valve Timing in chapter Valve Timing Technologies of Automotive Engine Design

Due to which factor, the valves can’t open instantaneously?(a) Inertia(b) Torsional(c) Momentum(d) Point loadI got this question in my homework.Asked question is from Valve Timing in portion Valve Timing Technologies of Automotive Engine Design