| First off you are mixing Psig, 174 and Psia 14.7. Second, I don’t think you can correlate your un-boosted pressure to boosted the way you did. If you take 14.7 Psia and multiply it by 8.2/1 compression ratio (I think I have no TT) you would only get 120 psia, or 105 psig at constant temp. All the rest of that increase that you see on your gage is due to an increase in temperature. I don’t think you can use your method to predict cylinder pressure.
Theorectically I guess a TT would be 29.7 X 8.2 = 243 psia
In reality it would be much higher but due to temperature Where an NA would be (I think) 10.5 X 14.7 = 147 psia All of this is in theory only since valve timing can obviously change the results. In any case volume and pressure are proportional so if you have 14.7 psia normally aspirated and you run 15 Psig boosted then you are effectively doubling your mass of air into the same volume. That would be true only if the temperature was constant.
The temperature change will have the opposite affect but it should be proportional. You should be able to ratio it up due to pressure, then ratio it back down due to the change in temperature and calculate the true ratio.
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