Background: I bought a BBC from a member here a couple years ago. Transaction went great and everything was packaged/shipped nicely. His brother built the motor and gave me several specs on it and said it was running great when he took it out. The engine sat on my engine stand for over a year (priming oil pump and turning over once every month or two with an occasional squirt of oil in the cylinders and replacing the plugs). I took the engine and put new tins on it with new oil pump, with matching pickup, and pan (Milodon), then installed a new timing chain and gear set (Edlebrock) even though the old one looked brand new and was tight. I put a matching SFI flywheel and SFI balancer (Rattler) on as well as new intake and carb, and GM Performance parts Serpentine drive. I primed the motor for 15 minutes with a drill and then installed. Right from the first revolution I could hear a noise in the motor. I ran it up and down a trailer (to the exhaust shop) and in and out of the garage but no more as I did not like the sound. This past weekend a buddy of mine pulled the valve covers and tried readjusting the rockers hoping that was the noise (thanks to another CK5 member for a set of old valve covers I cut up for catching oil). One thing we noticed were that several rocker arms were not getting oil and one rocker arm nut was different (not a big deal on the nut). The passenger's side seemed to be getting more oil to the rear arms while the driver's side seemed to get more to the front. The oil pressure gauge read 62+psi consistently (10W30 dino oil). The block has a cam oiler equipped in the lifter valley and we could see the cam getting plenty of oil through the holes the head. The noise definitely seems to be lifter/rocker noise. My question is would stuck/sticky lifters cause oil to not reach the top end? My buddy thinks that is the problem, but I'm not sure. I asked him how a stuck lifter would differ from a solid lifter. A solid lifter still gets oil up to the top end with no "pumping" of the lifter. My plan is to replace the lifters with new ones (and install hardened pushrods, guide plates, and roller rockers), but am I on the right track? I don't want to put it back together to find out the lifters weren't the cause of the lack of oil to the top end. Anyone know the flow of oil in a BBC and how much the hydraulic lifters affect oil reaching the top end? Sorry for the long post, but I would like to get this motor going after all the $$$ I spent on it.