Non-Detergent Motor Oil

[FrankWest]

I have an original engine car. The car was stored for 20 years without running.
When I purchased the car, I dropped the oil pan and it was not bad.. about and inch of sediment..that was like sand..not greasy sludge. I was told that that type of pan deposit is a result of running non-detergent oil. I got the car running and added a quart of MMO. Now I want to begin frequent oil changes to clean the engine.
Are you telling me that most of you guys running 80 year old engines use regular
bargan basement motor oil? I'm so confused.