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Cylinder Pressure and uncorrected vs corrected HP

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Currently live and tune at 8000-9000 DA levels at times so our uncorrected numbers are usually much lower than corrected numbers and cars tend to run almost a full second slower in the 1/4 mile here than at sea level.

Because of this, it typically takes much more for our cars to make power at this altitude. My question is, does 600whp UNCORRECTED at this altitude create more cylinder pressure and engine stress then 600whp would at sea level? Since we generally have to add more boost and timing to compensate for our altitude to create more power, does this equal more stress on components? Or, since the air is less dense here, would 600whp uncorrected still have similar cylinder pressures to 600whp at sea level all other variables being equal dispute it running more boost and timing?

hope that makes sense.


You've definitely got your work cut out for you at a density altitude of 8-9000'! Ultimately the engine doesn't really care what altitude it's operating at, and instead it's the cylinder pressure that defines how much power and torque it will produce. This means that on face value 600 whp is the same level of stress on the engine whatever altitude you make it at. The caveat here though is that you're going to need to work a turbocharger much harder in order to generate the same cylinder pressure. What you need to keep in mind is that for a given turbocharger, this is going to result in a lot more turbine inlet pressure at altitude than what you'd see at sea level so you will usually end up with the engine also working harder in order to maintain the same power level. For engines developed specifically for operating at altitude (Pikes Peak for example), you'd usually have different considerations with the turbo selection in order to level the playing field somewhat but then you tend to give away some response so there's no silver bullet unfortunately.