Just got down swapping my ls1 into my 94. Ran great all weekend while on vacation and on my return home, the oil pressure gauge started bounching all over the place between 20 and 40 psi at normal cruising speeds. Befor putting the motor in the car, i put on a portes ls6 which created excellent pressure. I figured that their must be something wrong with the sending unit because of how eratic the readings were. We pulled over, listened to see if there was any knock, checked the connections, ect. Everything seemed fine. After some more driving it seemed to start to steady out at 35-40 psi when crusing but when I got on it to pass somebody it would dip down to 20 psi. Once back, we hooked up the mechanical gauge and saw that the gauge in the cluster was really telling the truth. Changed the oil and filter to see if that would help, and it didn't, same issue. After cutting the filter open, their appeared to be some red, blue, and yellow makings which later turned out to be some markings that are made by comp on the cam. Also was some metal shavings but no more then we had ever seen in any filter that was breaking in some new parts (new lifters, timing chain, springs, push rods, cam, and rod bolts). So pulled the motor and trans out, pulled the pan down and saw nothing in it. The screen on the pick up tube had some items on it, looks like pieces of the oil filter elements. But still their really wasnt enough for it to impeed the flow of oil that drasticaly. We thought that some of the particles may have gotten past then screen so we decided to check out the oil pump. Thought that maybe some junk had caused the spring/valve to get stuck. After inspection, it looked perfect, no problems at all. So we then decided to spray some brakeclean down the oil inlet passage of the block. All that came out the filter inlet was just some oil and breakclean. So we replaced the oil pump and the pickup tube. Still in the process of getting it together but wanted to run it buy you guys here to see if you had any input. We think it may be a spun berring but I always thought knock/noise accompanied that issue.