Zinc additive

I would recommend not using both a Zinc additive and one of the high zinc oils. I have read some studies that indicate too much zinc / phosphorus (excess of 1600 ppm) can cause problems. Might not be one of those things where if a little is good a lot has to be better. I would run a break in oil that has the high zinc for the first few hundred miles on your new build and then run the high zinc oil after that (at least 12-1300ppm). The break in oil is usually petroleum oil while the high zinc muscle car oils come in both petro and synthetic - and a mix.