Thank you all for feed back. I called Rislone about ZDDP adaptive. I got engineer chemist on the line and wanted to know if it was harmful to aviation engines using ashlessdispersant . He said no worries and product was designed for flat tappets to prevent cam and lobe wear.
Since older Lycoming engines have flat tappets and wear more on cam and lifters I have started to add a pint of this product at oil change. I use victory xc 20w50 which has AW lyc additive also. Can there be any harm having too much zinc. On my latest oil analysis I see an increase in iron fe...