THIS IS ONE FOR YOURS TRULY, AND PROBABLY HAS BEEN DISCUSSED A TIME OR 2...… WELL OUT PLAYING POKER WITH THE FELLAHS OVER THE LABOR DAY HOLIDAYS, SO HAPPENS TO BE THE SUBJECT ON HOW VACUUM IN A NATURALLY ASPIRATED ENGINE ON GASOLINE WAS DISCUSSED...OK BOLTERS TECHNICALLY WHAT CREATES VACUUM AND WHAT IS THE OPTIMUM MEASURED FOR PERFORMANCE?