I recently replaced my timing gears and chain and distributor and Just put in a oil pressure gauge and new sender. When i first started the car with the new oil pressure gauge it read 50 - 60 now and slowly worked down. Now when i start it i have bad lifter noise for 10 seconds and it goes away and i idle at 25 on the gauge and slowly work to barely anything when driving. I have a 351 cleveland 2v STOCK btw. and the i put a mehanical gauge on first and it did the same thing so i though i hooked it up wrong but now my electrical gauge is showing similiar results. And yes i have the matching sender for each gauge. I was told by a guy in auto zone tht the clevelands had an oil distribution problem is there any truth to that and if not what could this be. Could my oil pump be going bad?