Shimming oil pump

[Mrkentee]

(02-24-2016 )Hedley Wrote:  your oil pressure seems a wee bit low, troubleshoot your oil pressure sensor and harness, you might have a bad sensor.

ps...make sure that you have the new Lubricating Oil Filter By-pass Valve installed...PN# 4357477

I used to run 30-35 psi, depending on temp. 35 at highway speed. And between 15-20 at idle. Also depending on temp. It's now 45-50, and at least 20 at idle. It is very sensitive to temp and rpm. (I will say the reading on insite was always 1-2 lbs higher than the gauge.)
What about this bypass valve? How is it different?