10 PSI is fine if you are reading it BEFORE the fuel filter. For me as my filter gets dirty I see less PSI. Reminds me to change my filter. I read my pressure at the input to the injection pump ie clean fuel side of filter housing. When my pump is working right I never get less than 12. 25 PSI @ WOT and pulling a 6500 5th whl with 22 psi boost. Take that for what it is worth. Keep in mind that less pressure (flow) means less cooling to your injection pump. According to the tech manual you should never see less than 10 PSI on the output of the transfer pump.