Oil Pressure Gauge, Is this right? Options

[6G96GT]

So I asked my mech to install an oil press. gauge and he did. I noticed it was tapped into the block and I asked him about the debris from the drilling if it would cause any scoring or anything. He said they grease the drill bit so the debris sticks to it or something and they use a magnet too. It sounds weird to me, is this accurate????

[6G96GT]

Alright, I got the car back today. Just drove it home 20 miles. My mechanic had to put a new flex pipe on with some new bigger piping as well. I had the Hi Flow cat installed at the same time with the header which is wrapped. It sounds good but not like I suspected.

Will it get louder and throatier eventually???

Also, what is the correct PSI at normal operating temp (at idle) for the oil pressure??? Mine is run from the head. It reads 10 PSI at idle and at 65MPH it reads 55 PSI steadily. It kinda seems low to me but I don't know. I checked the oil and it's at the right level and nice and clean. No leaks under the cars except for some brake fluid but that's an old issue.

[presure2]

Alright, I got the car back today. Just drove it home 20 miles. My mechanic had to put a new flex pipe on with some new bigger piping as well. I had the Hi Flow cat installed at the same time with the header which is wrapped. It sounds good but not like I suspected.

Will it get louder and throatier eventually???

Also, what is the correct PSI at normal operating temp (at idle) for the oil pressure??? Mine is run from the head. It reads 10 PSI at idle and at 65MPH it reads 55 PSI steadily. It kinda seems low to me but I don't know. I checked the oil and it's at the right level and nice and clean. No leaks under the cars except for some brake fluid but that's an old issue.

it may get a tiny bit louder, but not much at all.

oil pressure sounds about right..i get ~ 12.5 at idle.