Vacuum Gauges

[Simon.MATTHEWS@st.com]

     I don't like to burst anyone's bubble, but the idea that simply 
     keeping the vacuum high will improve fuel economy is not true. 
     
     Better economy will usually occur with the engine revs as low as 
     possible for a required output power. This implies that driving in 
     high gear (which requires opening the throttle wider, which implies 
     lower vacuum) gives better economy. If anyone doesn't believe me, 
     check out what various manufacturers have tried to achieve with CVT 
     (constantly variable transmission).
     
     Regards,
            Simon
     PS, if you want economy, drive a diesel!