The idle rpm increased because the engine is making more HP. Exactly what was expected.
So, when you switch off the engine, fuel leaks out of the pri shaft?
That could be leaking needle & seat { unlikely } or the o rings are not sealing. After switching off the engine, shine a light down the pri bore to see if you can see where the fuel is coming from.
Did you disconnect & plug the PCV? This cam is going to need more air & fuel to idle. So the fact that the pri blades are almost closed means the engine is getting air from somewhere. Make sure the sec blades are fully seated. That leaves the PCV [ not closing off at idle & letting a large amount of air into the engine ]; or air leak
