I would really like to know if the 15W50 is much better then w100. I have a C85-12 continental in my Luscombe. In the summer I use it about 20 hours a week so this could save me some coin! I don’t think the engine is using much oil but it sure likes to dump a bit of yellow foamy oil out the crank case breather once I shut it down. Does one type of oil resist foaming better then the other?
PT