Hi volume oil pump

Since I rebuilt my 340 I get between 20 and 25 at idle. But when you bring up the rpm's the pressure comes right up. At 2500 rpm's I have 50 to 55. I have always used a high volume pump with stock pan. I have had it up to 6500 rpm's and have never ran the pan dry. The oil pressure has always been over 50. This is my 2nd 340 which I have had a high volume pump and stock pan. I beat my car and have had 0 problems. I guess I've been lucky. It sounds to me that it's leaking somewhere. Maybe a plug is missing.

Fred