POR15 has the info on their website or you can call their tech line. Been a few years since I used it but when I built the coupes chassis seems they wanted "their" primer applied before the POR15 cured, then topcoat (theirs) after it all dries. I shot the por15 and then shot 2k primer over that while the POR15 was still tacky. I then scuffed and shot 2001 g.m. pewter base/clear over it. That was a good 5-7 years ago and it has never peeled or lifted. Buuuuttttttt then again the car is not finished and has not been subjected to the elements yet.