On my GMC I'm using ART's big red valves. For dumping air the valve is open at the bottom. I have air coming from the tank to the valves and then an airline to the wheels. I'm only using one valve for the front and one for the rear. I'm running 3/8 lines. I have a five gallon tank and just raising the truck to ride height lowers the tank pressure enough to kick the compressor on. If you put the compressor in hte trunk keep in mind that it is very loud. My compressor is under the passenger side of the cab right under my passengers feet. It can drown out my dual Flowmasters.