Power losses betweed N/A and Forced Induction

[redbeast]

Did some searches and didn't find the answers I was looking for.
I'm sure this probably has been brought up before but here goes:

I understand the power loss in N/A engines at higher altitudes.
How is it compared to Turbo and S/C engines.

Thanks

[Tik-Tok]

Generally speaking naturally aspirated engines lose 3% every 1000' above sea level.

[Mr_ET]

Every car regarless of N/A or turbo loses power at our altitude but it is much easier to get the power back on a turbo car.

[alloroc]

Turbocharged engines do not lose peak HP at higher altitudes though lag may slightly increase and they will lose power at the lower end of the rpm range.

Both Supercharged engines and normally aspirated engines lose power at higher altititudes.

The difference is that you can build the supercharged engine to obtain optimum performance at the higher altitude by supercharger selection and Supercharger RPM.

You may want to check the web or your local library for this book...

Synthesis of Subsonic Airplane Design
by Egbert Torenbeek

It covers this subject very well.

[rage2]

Originally posted by alloroc
Turbocharged engines do not lose peak HP at higher altitudes though lag may slightly increase and they will lose power at the lower end of the rpm range.

It depends on how the wastegate is managed. Your case is only true where the boost pressure is controlled using an absolute pressure signal. If the wastegate system is setup to control boost based on difference from atmospheric, it'll still lose power at altitude.

[The Cosworth]

Originally posted by rage2

It depends on how the wastegate is managed. Your case is only true where the boost pressure is controlled using an absolute pressure signal. If the wastegate system is setup to control boost based on difference from atmospheric, it'll still lose power at altitude.

I never thought about it that way but your right.

+1 for rage's comment