Charged Air Aftercooler

Yes, in my opinion you are Overcooling the air.

Under normal standard operation where the cooling water is used, the compressed air does not cool down below the coling water temperature which is above 176 deg F. therefore, you should not drop down below that.

After cooling removes energy from the compressed air and a balance is achieved between the benefit and the losses to have an increase of the power generated by the combustion (increasing the fuel intake because more air is available...). Do not cool down below 185 F

You have achieved moving the compressed air water from condensating on the outside of the line to the inside of it.I think you have an air leak.

The outside air is at RH70% and it will only increase in temperature when cooling the compressed air after the turbo, therefore, the RH% will drop since it is the same air being heated, and this will prevent condensation of the outside air... Also, the inside air is at a higher pressure, preventing the outside air from going in --> no air leak into the compressed air.

The condensation will occur within the compressed air line if the pressure is high enough and the temperature is low enough. Therefore, compressing the air to 35 psi (2.5 times the atmospheric~), and then cooling it to 100F, is probably enough to condensate some water from a 70%RH at 86F source. If there is a chart for this pressure / temperature, you can consult it Or if able to calculate the state. I don't have a chart but would think it is near enough.

mainly, why cool it that far? It is not done on normal engines as far as I know. So keep it hot enough to prevent condensation, and cool enough to have the air density required for more combustion...