2H Hi oil pressure

[Davetavita]

I have a 2H-T motor which was fully rebuilt now with 30k kms on the build.
It received the longer oil relief valve upgrade during the build.
On cold start the needle on the oil pressure gauge is between high and walking off the gauge.
There is a constant tapping sound when powering on and drops away when I lift off the pedal.
When the engine reaches operating temp, oil pressure sits on high the noise is not there.
Any ideas please?

 

[duncanrm]

The tapping sound on power on.. consider an exhaust leak.

For the oil pressure, It doesnt sound concerning, it'd be great to get a test gauge on the system and get an actual reading in PSI though.