i am goin to install fuel and oil pressure gauges in my integra, is there any difference in the performance of the gauge if it is elec. or mech. also i have a aem wideband gauge i need to know if the #s on it are a ratio or a # with a decimal and if so wat does the # read , air? or air and fuel? and if i have this guage do i really need the fuel pressure gauge? the reason i am asking about the #s on the gauge is because it jumps around like its counting, for example 13.9 to 14.1, everyone is telling me that its reading 13 lbs of air to 9 lbs of fuel but if it goes to 14.1 its just doesnt make sense to me .