360 engine how far should oil pressure drop at idle?

10w30 oil, 20 psi hot idle 650 rpm in drive stopped at traffic light. 60 psi driving, high performance engine was built about 7 seven years ago, in the car when I purchased it five years ago, not many miles on it. Auto Gauge direct reading gauge. Thanks to all

20 PSI at 650 hot with 10w30. I'd say you're good to go.