[cadillac_al]

My opinion is that the old 230 with stock small cam and light valve springs can run just about any oil. I am also of the opinion (shared my many others) that ZDPP isn't the only consideration in whether an oil can perform its duty. I think the 230 would be happy with any name brand oil anywhere from 10w30 up to 15w40. When you get into high performance high lift cams and stiff valve springs then you will have a reason to research higher quality high performance oils. Just my .02