I was driving home form Anger managment today and was thinking about anothe r post of mine. The Subject was air intercoolers and if it would be benifit or not. I decided that without a turbo or Super charger it would be worse off. Then I got to thinking of what the difference is between a turbo and a vacum. The only thing I could think of is that the amount of boost is regulated by the RPMs. Now I am not saying I am going to go and put a vaccum in my car Ijust thought I would throw the concept out there because the vacum would take less power from the motor to produce boost then a turbo would.