my 454 is running around 48-50 psi at idle. is that cool??

Yup.
10 psi per 1000 RPM's is like minimal....so as long as you get 15-20 at idle (hot), and it goes up with RPM, you're golden. http://www.nastyz28.com/ubb/smile.gif

BTW....how high does it go when you rev it to 4000 ??

hot or cold idle?

Just when I started it up. Ran it for about 5-10 minutes. stayed around there. The tap for the guage is at the front lower of the engine.

Check it hot.

Sounds fine. My 350 has a Z28 high pressure pump (different pressure relief spring) and I see 70-75 on a cold start, 20-25 warm.

Drive at around for 15 minutes and see what it does at idle.
Oh, and if you live near the highway like I do, be aware that unless you have overdrive or 2.73's, your idle oil pressure will be a touch lower at idle right after coming off the highway untill the oil has cooled a bit.

468 BBC high volume pump 20 psi idle hot, 60 psi at 65 mph hot, cold idle 45 to 55 psi. Like the guys said 10 psi per 1000 rpm minimum and drive it.