Why not buy an oil pressure gauge and stop all of this guessing, unless it is not that important. Gauges are cheap and you can install a "T" fitting on the back of the block under the sending unit and have both. An idiot gauge where you hope you are guessing the correct pressure and a direct reading gauge, calibrated with actual pressure readings. Done. If you really need these weird high viscosity oils, You need to plan on a rebuild when you get home.
