Turbocharge

Question 1

Turbo definition

Answer 1

Turbochargers were originally known as turbosuperchargers when all forced induction devices were classified as superchargers. Today the term “supercharger” is typically applied only to mechanically driven forced induction devices. The key difference between a turbocharger and a conventional supercharger is that a supercharger is mechanically driven by the engine, often through a belt connected to the crankshaft, whereas a turbocharger is powered by a turbine driven by the engine’s exhaust gas

Question 2

Manifold pressure

Answer 2

•DECREASES 1 INCH PER 1000 FEET
•RATED HORSEPOWER IN UNBOOSTED ENGINE IS ONLY AVAILABLE AT SL

•LOSE 3% PERFORMANCE PER 1000 FEET

Question 3

Turbocharging theory

Answer 3

Extracting more power out of an engine by increasing the density of the air that goes into it, therefore allowing you to add more fuel and increase your power output.

Question 4

Turbocharger vs supercharger

Answer 4

Turbocharger
●Driven by exhaust gases from the engine
Supercharger
●Mechanically driven by the engine through gears or belts

Question 5

Ground boosted engine

Answer 5

An engine that can be boosted to well over the typical 30” of MP.
Normal range is from 38” to 43”.

Question 6

Altitude turbocharged engine

Answer 6

An engine where the turbocharger is only used at altitude.
Engine does not have to endure internal stresses any greater than normally aspirated engine.
Typically limited to 30” MP.
Compression varied by Waste Gate

Question 7

Wastegates

Answer 7

Adjust the amount of air pressure available to an engine
If wastegate is closed, the maximum amount of compressed air is available to the engine
If wastegate is open, the exhaust bypasses the turbocharger & the engine runs like a normally aspirated engine

Question 8

Manual controlled wastegates

Answer 8

Used normally above 5,000’
Uses a vernier control to maintain manifold pressure
Remember to open wastegate during descent

Question 9

Fixed wastegates

Answer 9

Simple operation
No extra controls
Allow only a fixed amount of boost

Question 10

Automatically controlled wastegates

Answer 10

Adjust the wastegate automatically to maintain desired manifold pressure
Requires smooth application of power to prevent over-boosting

Question 11

Operation of turbocharger

Answer 11

Care must be taken to prevent power surges and over-boosting of a turbocharged engine.
It is especially important to increase propeller control before the throttle/wastegate
Decrease the throttle/wastegate before the propeller control.
Monitor CHT gauge & use 100 Octane fuel as a minimum or the minimum the POH recommends.
Turbocharged engines are more susceptible to detonation.
Mixtures are normally run slightly richer than normal.
Refer to POH for exact operating instructions for your turbocharged engine.