Multiply the sea level compression reading by the FACTOR to see
what it would be at the ALTITUDE. Multiply the altitude compression
reading by the INVERSE to see what it will be at sea level.


ALTITUDE FACTOR INVERSE
1000ft .9711 1.0298
2000ft .9428 1.0607
3000ft .9151 1.0928
4000ft .8881 1.1260
5000ft .8617 1.1604
6000ft .8359 1.1963
7000ft .8106 1.2336
8000ft .7860 1.2723


examples
Compression in psi at sea level = 125 What would the reading be at 7000
foot elevation? 125 x .8106 = 101.325

Compression in psi at 7000 foot elevation = 115 psi. What would the
compression reading be at sea level? 115 x 1.2336 = 141.864.


"Volksrod70" > wrote in message
m...
> Does altitude have any effect on compression ratio?
> I'm at 5200 feet.