That pressure is too low. Especially with a fresh engine.
Does it sound noisy? Like lots of lifter type sounds?
The inner 2 cam bearings can fail on a new engine, then they hemorrhage oil around them causing a oil pressure loss.
It is one problem to think about.
Here it is in more detail. Near bottom of my page. You may be able to see if it a problem using a scope or good mirror thru the fuel pump hole and look at the cam bearing.
https://www.12bolt.com/tech-tips.htmlCam Bearings
Keep in mind when changing cams to pay attention to the bearings. Here is a abbreviated article from King Bearings on Cam bearing failure.
Structures and Materials of Camshaft Bearings
The typical structures and designs of camshaft bearings are presented. The most traditional design of camshaft bearings is a steel tube with a layer of lead based Babbitt alloy applied onto the inner surface (bush type camshaft bearing). The bearings of this type may be supplied in semi-finished (un-bored) condition. Then the bearings are bored after installation in the engine. However, the precision (bored) finished type is more popular. A relatively thick and soft Babbitt layer provides good conformability of the bearing. The material allows fitting its shape to misalignments. Babbitt also has very good embedability, which is important for bearings operating with contaminated oil. The main disadvantage of Babbitt bearings is their low load carrying capacity. Babbitt alloys are soft; therefore they have low fatigue strength. Also, the fatigue limit of the lining is directly dependent on its thickness: the thicker the layer the lower its fatigue limit. Since the Babbitt lining is relatively thick, its fatigue strength is low (~2,000 psi). Bi-metallic camshaft bearings, with a lining made of aluminum alloy, have a much greater fatigue strength of at least 5,800 psi. The bearings are split shells type, rather than bush. King Engine Bearings manufactures camshaft bearings made of aluminum/silicon alloy: K-788 . Their load capacity reaches 8,000 psi.
A bimetal structure with an aluminum alloy lining is the best solution for camshaft bearings. Aluminum alloy is not too hard, therefore it has good conformability. Also, it is stronger and more wear resistant than Babbitt. In contrast to a tri-metal structure, aluminum alloy bimetal bearings have superior conformability, and can tolerate far greater wear since they do not have a thin overlay. The thickness of the aluminum lining is approximately 0.010”. If the load applied to camshaft bearings exceeds the fatigue strength of aluminum alloys, tri-metal materials having a copper based intermediate layer and very thin (up to 0.0008”) soft Babbitt overlay are used. Tri-metal materials have greater load capacity, but their conformability and maximum wear are limited by the very low thickness of the overlay. Once the overlay is locally worn out and the bronze intermediate layer is exposed, seizure of the bearing by the steel journal becomes very probable. Since misalignment and excessive wear due to oil starvation are typical causes of camshaft bearing failures, tri-metal construction is rarely used in the design of camshaft bearings.
King Bearings are made using the K-788 Aluminum/ Silicon Alloy. These are the bearings I recommend.
Pictures of failed cam bearings. Notice how the soft babbit flows over the oil hole.