State the difference between turbocharger & VGT used in diesel engine.

State the difference between turbocharger & VGT used in diesel engine.
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1 Answer

Answer :

Difference between turbocharger and VGT

Sr. No.
Parameter
Turbocharger
VGT
1 Fuel efficiency
Lower fuel efficiency as compared to VGT
Improved fuel efficiency by20%
2 Turbo-lag
More Turbo-lag
Reduced Turbo-lag
3 Power output 
Lower power output at lower speeds 
Higher power output even at lower speeds
4 Boost pressure at low speed
Low
Adequate
5 Boost pressure at high speeds
Increased boost pressure, requires waste gate boost control
It is not excessive so waste gate boost control is not required.
6 Engine response
Sluggish response at low speeds
Quick responsive engine
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