for elaspsed time and horsepower for altitude conversion? Thanks

found it...

tell me

Yeah, don't leave us hanging..........

HP loss is based on weight/volume loss of air by temperature at increased altitude or commonly refered to as air density loss.
There are lots of ways to compute this loss but you need the exact air temp and altitude to get it correct.
There is a simple basic equation to fiqure HP loss at altitude based on an ambient temp of 68* F using the following air pressure chart;

0 14.70 (Sea Level)
500 14.43
1000 14.18
1500 13.92
2000 13.67
2500 13.42
3000 13.17
3500 12.92
4000 12.69
4500 12.45
5000 12.23
5500 12.00
6000 11.78
6500 11.56
7000 11.34
7500 11.13

Divide the air pressure of the altitude you are at by the air pressure at Sea Level and then Multiply it by your HP rating to get a rough HP loss. The example that follows would be for a 500 HP engine at 3500 ft above sea level;
- 12.92 / 14.70 = 0.879 X 500 = 439 HP @3500 ft

Again this is a very basic example of the Air Density/HP Correction equation, but it will at least give you a base to go from. As air temp. increases the density decreases so you would need adjust the pressure value. Plug the HP figure you get into an ET calculator and you will get an estimated ET for that altitude.

If I ever do find my nifty chart in my old computer I will post it. But math you can carry everywhere with you - computers are a b1tch to lug around.

Hope this helped?