Boost at Different Elevations

[Nytroman]

I have a question regarding boost vs hp vs elevation on a MCX Nytro. At 12psi boost at 2000 feet sled puts out X hp. At 7000 ft at 12psi boost, is the HP still equal to X. Does a turboed machine need to run higher boost at higher elevation to acheive same HP than at lower elevations, and does it need higher octane fuel at sea level than in the hills at the same boost like a high compression 2 stroke. I was told that the MCX kit compensates to keep the boost consistant at all elevations, but the HP drops when at altitude, and that the compensater should not be used or the waste gate would need to be tightened up when in the hills.
Just hearing two sides of the coin and want help verifying it
Thanks for some info.
Nytroman
PS What event is going down in Revy this weekend

 

[SLY]

The compensator will actually increase your boost pressure at elevation to compensate. The idea is to maintain the power level, not the boost level. So, while you may see 12 at 2000' you may see 13 or 14 at higher elevations. The oxygen content is less at higher altitudes but if you're running boost you probably won't notice it anyway. The power loss is not as noticeable with a turbo because the impeller will still spin and compress air until it reaches your wastegate setting anyway. I'm not sure on the octane at elevation calculation but I think that you can get away with lower octane fuel at higher elevation because of the lower oxygen content.