I didn't see anything posted directly about my question using the search so here goes.

High altitude has a drastic effect on NA motors but what about Boosted motors?

If I were to install a supercharger or a turbo and run on preset boost of 8psi, would I see less boost where I live at over 5000ft?

I've also heard that high altitude may affect the amount of boost produced on supercharger more so than a turbocharger, is this true and how much of a difference?

Gurus please offer your input, i'm really interested to know.

Thanks in advance.

 

I'm not sure???
I'm going to speak from a pilot's perspective....

I do know that normaly aspirated engines tend to lose significant power above 7,000f
Thats why most GA airplanes that operate above 5-8000f are usually turbo-charged or super-charged....

For example with my bird:
I can climb to 5000f in approx 6 mins (@ 25 in Manifold press) from 5000f to 7000f it takes another 7mins....to get to 10,000f from 7000f usually takes 15mins!!! and by the time I get up there, my max power output is down to 12-14 in of manifold press!!!

Now does a turbo/supercharger lose pwr at high altitudes???
I"m sure it does, but I cant tell you by how much!
Cheers,