I believe the book calls for .040 for plug gap but it has alot to do with how you run the motor it is not etched in stone. It may run better at .030 or .035. You will find out what does best for your setup by checking the plug colors and trying different plug gap if .040 dont seem right. Keep a tab on gallons per hour running the motor at full timing advance. WOT will always suck down the fuel just watch the timing advance with the engine off and in forward gear put a mark on your controls at the point the trigger stops moving. You allways get the best economy at that point.
