Quaker state Q racing oil, and Joe Gibbs racing oil, has the most zink, compared to any of the others. Rotella, when it had more zink than it does now, they revised the formula for epa b*llsh*t, had about 1450PPM, (parts per million), of the good stuff. Quaker state Q, has about 1950. Joe Gibs, has almost 3000!! Thats why all the nascar teams are using it these days. One other thing, my sources say, that GM took most, if not all the zink out of EOS, as the epa said to.
Frank
Advanced Performance
www.get-ap.com