Which type of oil to use

I realized that after.

I have thought about running 50 weight in my warn out dart as the running oil pressure at temp is on the low side. I was using 30 weight but I went to 40 weight because my oil light kept coming on when I would come to a stop at a signal. does not do that with 40 weight, so the 40 weight increased my oil pressure by at minimum 1 psi :rofl:
I tried 20/50 in Vixen. She would not idle cold. You could tell the oil was holding it back terrible when cold. I couldn't believe it.