Quote:
Originally Posted by Blackdog_kt
There's two more things you might want to keep in mind. First one, just like you observed yourself, if you are running at a certain manifold pressure and RPM and then decrease the RPM by a large margin, you'll see that the MP increases. I don't really remember the explanation to this, but it happens in real life so that's good enough for me to have it in the sim  |
Throttle affects how much air is let into manifold, and engine RPM affects how much air is sucked from manifold (in time frame). Less RPM, less air sucked, less vacuum created -> manifold pressure increases. ~
However, less RPM do not always result in higher manifold pressure. Too slowly turning engine won't drive supercharger fast enough and you will see manifold pressure dropping towards ambient pressure even with full throttle open. This is very noticeable at high altitude, where you need to run your engine at high RPM or supercharger won't provide max boost anymore.