This subject is old news but the extent to which it has been applied isn't. As most of you probably know the new standards for oil call for a substantial reduction in the level of zinc (ZDDP) in oils because the zinc causes deterioration of cat's. For those of us with cars that have flat tappet cams this a major problem. Zinc is absolutely vital in preventing premature cam failure and other wear issues, expecially in HP and race engines.
What many of you may not know, judging by how many guys I run into who do not know, is that there are very few oils left that have a sufficient zinc concentration to properly protect our engines. Most of the major manufacturers have reduced the ZDDP in all of their oils including synthetics to levels WAY too low. Mobil introduced the new Mobil 1 15W-50 to address this issue but pretty much none of their other oils are much good to us any more. Contact the manufacturer of your favorite oil and ask them what the ZDDP concentration is in the oil you are using. If it is less than 1200ppm, or if they will not tell you what it is, stop using it NOW. The 1200ppm figure seems to be the concentration agreed on by most of the major cam manufacturers as a good minimum. You can contact them to see what they say about this.
There are some alternatives out there. Amsoil is a great one. All of their synthetics have a ZDDP concentration in the high 1300's. Royal Purple has a good product too. Right now you can use diesel oils like Rotella, Delvac, and Delo but with diesels starting to use cat's the ZDDP will disappear from them too soon and you will not know when it does. There are also cam break-in and ZDDP additives like that from Hughes engines and others but a lot of people are uncomfortable with additives because of possible inconsistancy and foaming. I have no experience with them so I don't know how valid either concern is. The bottom line is that you may not be able to rely on your old favorite any more. Check it out to be sure. 1200ppm minimum, 1300-1400 is best.
What many of you may not know, judging by how many guys I run into who do not know, is that there are very few oils left that have a sufficient zinc concentration to properly protect our engines. Most of the major manufacturers have reduced the ZDDP in all of their oils including synthetics to levels WAY too low. Mobil introduced the new Mobil 1 15W-50 to address this issue but pretty much none of their other oils are much good to us any more. Contact the manufacturer of your favorite oil and ask them what the ZDDP concentration is in the oil you are using. If it is less than 1200ppm, or if they will not tell you what it is, stop using it NOW. The 1200ppm figure seems to be the concentration agreed on by most of the major cam manufacturers as a good minimum. You can contact them to see what they say about this.
There are some alternatives out there. Amsoil is a great one. All of their synthetics have a ZDDP concentration in the high 1300's. Royal Purple has a good product too. Right now you can use diesel oils like Rotella, Delvac, and Delo but with diesels starting to use cat's the ZDDP will disappear from them too soon and you will not know when it does. There are also cam break-in and ZDDP additives like that from Hughes engines and others but a lot of people are uncomfortable with additives because of possible inconsistancy and foaming. I have no experience with them so I don't know how valid either concern is. The bottom line is that you may not be able to rely on your old favorite any more. Check it out to be sure. 1200ppm minimum, 1300-1400 is best.
