| post came up, I have been considering putting it all together and showing exactly why the SAE correction doesn't work for FI Intercooled setups. Your response is good, it is probably the straw that will break this camel's back and force me to show exactly what is going on. :) Just off the cuff here as a quick explanation of what all is involved: Lower atmospheric pressures reduce air density.
Boost gauges show you gauge pressure, not absolute pressure.
The difference in absolute pressures (under boost) will cause the turbo to operate in a different range of its compressor map, and we can easily determine the difference in efficiency.
The intercoolers are boosting efficiency and we can use a general efficiency value for them to allow us to proceed with the calculations.
From this information, I can show you why the SAE correction factor does not apply very well to FI Intercooled systems when you change the altitude at which the tests are being performed.
I have all of the ECU's algorythms memorized and showing how the difference in atmospheric pressure will affect what region of the fuel map being used, as well as showing the reduced enrichment used in these areas will seal the deal as to why these cars are running leaner values. It really isn't all that complicated.... I have just been avoiding having to put the facts out there as it will come as an insult to those who just dont agree, which will only further increase the tensions. With this in mind, do you think I should take this challenge? Arts numbers are with JWT boost jets, which dont run at 15psi. They run more like 13.5psi. Add to that the fact the ambient pressure is only 12.5something psi, he only has ~stage4 mods with stock intercoolers, and I will say all day long that 351RWHP is absurdly high.
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