recommended oil for '68 383 ?

I'm with Rusty on STP treatment. I have had great luck using it. Tried Lucas oil trestment didn't work so good. I run 30wt straight vr1 valvoline has zinc. 3 or 4 months ago got a case of brad penn 30wt straight. Am going to try it out. Got a good deal on it. Probably still use stp for insurance!:) read somewhere that brad penn has a little less zinc than vr1.