Are you having drivability issues with every non stock fuel pump? These are some of the specifications that should be checked when buying a fuel pump.
1. Flow (volume)2. Pressure3. Voltage
At times, defective or weak fuel pumps are passed as okay simply because the technician feels that the pressure is okay. As engine load/horse power demand increases, there is need for more volume of fuel. Hence, a pump that appears to have sufficient pressure may not be able to meet up with volume demand.
Ensure that the new pump meets the pressure and volume demand of the car.
Note that some pumps are volume rated at zero line pressure. When fitted into the car, restrictions will be introduced and volume will drop. Hence, that volume rating is not practical when the fuel pump is in operation..