In article , Friedrich Ostertag wrote:

basically, MP should not change with altitude at all, at least as long
as we are talking absolute pressure. To maintain a certain power at a
given engine speed, you need to have the same amount of air mass going
into the engine. As the volume of air the engine sucks in is determined
by the displacement and does not change, the density needs to remain
the same also, hence the pressure in the manifold stays the same.

Ah. Got it now. Thanks.

Am I wrong or are the tables bogus?

The tables are correct.

I figured the tables would've been corrected by now if they were wrong.


Morris (writing down the ideal gas law on the blackboard 100 times)