It is louder but I can't hear it when the car is on, from the inside atleast. I haven't noticed any increase or decrease in performance. How many of us are really using/pushing our fuel pumps to limit. 1 aeromotive 340 is suppose to handle 700hp, it also says in the aeromotive instruction that the stock wiring will not allow the pump to flow at the rate of 340lph. You have to make your own circuit with fuse and relay using 8 gauge power wires and ground wire, and believe me the pump is much louder. Wouldn't it be more beneficial to put the pump on its own circuit with the relay being activated by the ecu and just eliminate the problematic fpc and fully utilize your pump? Just asking.