My builder used the pressure relief valve to adjust/increase my pressure. Just a thought, when I put my engine back in the car my Smith's
oil guage read 20 psi at idle hot. Obviously I was concerned and brought the car back to the builder and we ended up sticking an pressure gauge in the same port and discovered mine was reading 12 psi low! So now I have to simply add 12 psi to whatever the guage reports. This might be the case with yours and is relatively easy to check. Best wishes!