I have done as much reading on this subject as I can find. I also have some personal experiance with the oils commonly available today. What this research found is a very high failure rate for Flat Tappet Cams. It has gotten so bad that when I had Pat build my last motor a SBC I used at Pats recommendation a roller cam. I also have built a couple of BBC Chevys and have learned by listening to guys that really know there way around BBC's that a roller is really the only way to go in that engine period.

I also talked to just about all of the Cam manufacturers. Without a doubt what all of them told me was that a stock motor or one close to stock can get by with a additive pack of as low as 850 PPM they would prefer 1,000 PPM of Zinc Phos. But if you are using an aftermarket cam that requires a higher pressure spring and a more aggresive cam profile that nothing less than 1200 to 1300 PPM has any chance of letting the cam live.

paul274854, If you are using Rotella and think it is giving you protection than thats fine with me. I don't think it is, and I am not trusting my investment to a oil that at best is borderline by the recommendation of the guys building the cams.

RS