Hypro Diaphragm Pump D403GRGI with GX160QH Honda Engine Hypro D403 diaphragm pump with max. 10.6 GPM, 580 PSI, 3600 RPM, 140 deg. F temperature Honda GX160QH gas engine is rated at 4.8-5.5 HP Ports: 1" inlet, two 1/2" NPT hose barb outlets. Includes regulator (pressure relief valve) and gearbox (to facilitate coupling with engine).