Figuring out Dynamic compression

pjc360 said

That makes sense, so with every cylinder reading 150psi at my elevation of 4000 feet above sea level, what would the reading be at sea level?
I've been told the thinner air at 4000 feet above sea level will put out a lower cranking psi on the gauge vs if it were at sea level.

Click to expand...

That is right. Your setup would end up around 175-180 psi at sea level.

Just be aware that this is all computed numbers; at least in your case, there is a 4000' number to start from. But there was a recent discussion where these type of computations showed maybe 175 and a poster (an expereinced guy BTW) swore by a consistent 195 psi. So that 'modification' factor to the pressure rise is variable; I forgot to ask in that thread if those readings were hot. I assume your readings were taken cold....Yes? No?