I have a 98 Silverado k1500 with a 383 stroker with about 10k-15k miles on the motor. I have a high pressure high volume oil pump. Usually I would have 50 - 60 psi at idle. Around 80 psi at 3k and above RPM. I had recently changed the oil pan gasket, rear main seal, timing cover. No leaks now. My oil pressure now is about 5 - 8 psi at idle to about 20 psi roughly when I go above 3k RPM. I put in a mechanical oil pressure gauge. The mechanical and electric pressure sensor were the same readings. I pulled the distributor and put in my priming tool. With my drill at full speed I get up to 50 psi at my mechanical gauge. Thought it might of lost prime or caught air. Reinstalled distributor, and checked oil also. Oil is clean and fresh. New oil. Turned on and got the same result. By using the prime tool I eliminated the oil pump being bad. Could I have a clog in my system? I have an oil cooler also. I was thinking about eliminating the oil cooler and filter housing. Process of elimination. Going to replace the oil filter and open it up to see if it has something in it. I use the AC Delco oil filter and 5w oil. Any suggestions on what else I can check. Thank you in advance.