Pull the cowling and check for a clog on the hose between the P hose and the motor. Those motors do not do well on fuel. You can gain speed with a 25 pitch Fury or Tempest but you may not like the planning time.
“The world will not be destroyed by those who do evil, but by those who watch them without doing anything” Remember what He has done and remember that He is not done yet! GOD IS GOOD