It appears to me that velocity is not defined as blender units per frame/step in the game engine. What exactly is the definition? Blender Units per second? Blender Units per x frames? etc

Offhand, I think it’s blender units per second. This would fit in with how Bullet probably represents it, as meters per second.

I aggree with Raiderium.

Physics are calculated per second, however, if you add acceleration in a python script: that will be adding per frame so you will need to divide it by the average frame rate (GameLogic.getAverageFrameRate()).

Oh, I didn’t even think about using the average frame rate, I was just basing it off of 60. Thanks for the tip!