Non Detergent effects on Babbit? I don't know but we ran a 52 Chev 1 1/2 Ton truck with a 216 and Babbit for years on detergent and had no problem with the Babbit. However we did use a good grade of Detergent oil and changed it frequently. The biggest thing to remember was you couldn't wind the engine up. RPM is Babbit bearings biggest killer (unless you have a head gasket leak and get antifreeze in the oil which will knock out bearings in no time). As long as you change teh oil and filter often you don't have to worry about plugging up the filter. Besides if you are plugging up the filter you sure are not changing the oil ofter enough. On a good engine that has been rebuilt and in good condition the oil shoul only be slightly colored when you change it. If it is black you have definitely waited to long to change. The new cars and trucks have better oil filtration and air filters that the old engines. A paper filter filters out a much higher percentage of dirt from the air than an oil bath. As long as you don't wind a babbit beater very tight and keep the oil clean they will do OK If you use dirty oil and let the dirt help wear out the babbit and let them get loose where the rods hammer it they won't last long. As long as there is a good cushin of oil between the crank and the clearance between the babbit and crank is ok the babbit won't beat out and the crank and babbit won't wear. but any dirt will act as sandpaper and wear both surfaces but this happen on both babbit and inserts (which by the way has a thin layer of babbit on it to ach as a sacrificial material if the oil is dirty or on dry starts so the crank isn't damaged) Just remember these engines wern't designed for interstate, 40 to 45 MPH were the typical sppeds back then and the leadfoots might push it for a while before they threw a rod.
