Okay joined today because I've had about enough of reading about flat tappet cams and what engine oil is suitable. First thing, is I've an old Y-block Ford engine with solid lifters. It was overhauled some time ago and has excellent oil pressure and flow. Valve spring pressures are not radical, stock cam etc. For the moment, let's leave aside the question of whether ZDDP or elevated zinc/phosphorous is even necessary. What I'm looking for is a readily available gasoline engine rated motor oil in 10w30 with a normal oil change interval of 5,000 miles or near enough, and doesn't cost $17 a quart. For many years I never paid any attention to it. The Zinc Question that is. Always been pretty good about oil change intervals. After a bit of reading on the subject, I then switched to Rotella T for a while, 15w-40, and it's a good oil - but after installing a new oil pump and gauge it looks to me the engineers got it right, the lightest viscosity oil that maintains good oil pressure when hot will also have good flow. Rotella has lots of "detergents", which is good, but I'd just prefer a modern high quality oil with a little extra zinc for peace of mind, and an additive package designed specifically for gasoline engines that has sufficient detergents/dispersants anti-foaming agents, corrosion inhibitors, blah blah blah. Maybe there is a "Diesel" oil that is also S (spark engine) rated, I dunno. I don't want to make a career out of this. I have VR1 10w30 dino oil in it now. Not outrageously spendy, has Zinc, but it is "racing oil" and per a phone call with Valvoline is only good for 3 months/3000 miles. The 3000 miles doesn't bother me, the 3 months does. It doesn't have an additive package designed for extended oil changes. I think once or twice a year is fine, I don't drive it that often. The problem seems to be that simply because a motor oil contains Zinc, that doesn't necessarily mean they are using a good quality oil to begin with. Marketing. "Break-in" oil is not really a good choice, and additives in a bottle aren't a panacea either, as motor oil is a carefully blended package yadda yadda. I don't want to install oil additives. I've had it reading these oil threads on the intertubes. I'm just a simple guy trying to do a simple job. When I was growing up we just grabbed a yellow can of Pennzoil and tried not to spill on the exhaust manifold because it smelled funny for a while.