This quarterly report documents work performed under Tasks 10 through 14 of the project entitled: Technologies to Enhance Operation of the Existing Natural Gas Compression Infrastructure. The project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity. The report documents the second series of tests performed on a GMW10 engine/compressor after modifications to add high pressure Fuel and a Turbocharger. It also presents baseline testing for air balance investigations and initial simulation modeling of the air manifold for a Cooper GMVH6.