Oil line plug/ low oil pressure on cold starts

Stock 318 with high rpm lifters. Gotta ask what is going on?
If this 318 has been worked, then I don't know if those lifters are needed but as far ZDDP, I'd want a minimum of 800 ppm for stock cam, and maybe a bit higher, more like 1200 ppm if the valve spring pressures are high for a more aggressive cam. So if the oil you're using is has that in the additive package there's no reason to add more. Save your money. Oil is expensive enough these days.