So for almost a year I am trying to bring long term sleeper car to life. One of many but by far biggest problem was corroded engine block. I managed to get other block and do the swap. The car has 18.000 miles and condition of pistons, bearings, rings and other internals would be testament to that.
However, since engine block swap the oil pressure is running low. It used to be 80 at 2000 RPM now is 40, with just touch above control light on idle.
I use mineral 15W40, changed oil already and replaced the pressure senders so neither oil nor measuring instruments are at fault I think.
What did I do wrong?