[Adger Smith]

Ben,
To add to the problem of no Zinc as Bob said was the multi Viscosity oil. 10W-30 is not 30 weight oil & doesn't have the same shear or EP rating as a single weight oil. When I put an engine on the dyno it has a heavy single weight oil in it. Or it has VP break in oil in the engines with real lite ring packages. I never use a synthetic for inital start up or break in. These older engines we are racing with had oil systems that were designed before the thin oils became the vogue. Unless you build the clearances correct for thin oil (read that Multiple viscosity oil, too)I feel you are just asking for trouble using it. The way a cam gets oil is by what is tossed or spun off the crank, Rod side clearance helps. Then we put better pans & scrapers that remove this rope of oil from the crank, to cause more lifter/cam oiling problems. The other way a cam is oiled is small amounts of oil that sheds from around the lifter and drips on the cam. We reduce this by having tight lifter bores & some people still think they need oil restricters in the lifter passages. I've seen a flat cam In almost every case that I've seen backyard or Magazine engine builders block the oil drain holes in the lifter valley. I've also seen it in late model engines that are designed for roller cams and a flat lifter cam is used. Most of those blocks don't have drainback holes along the cam in the valley. What does blocking those hole really do. I think it air locks the upper part of the cam tunnel. How can oil get thrown from the crank into that area on top of the cam where the lifters ride when it is in an air lock? Common sense and careful preparation along with the right lubricants keep cams from going flat. I stay away from the tricks of the week that makes 2 more HP & cuts engine life by 50%. One more thing I preach to customers is IDLE TIME & SPEED. Low idle times & high Idle speeds keep cams & lifters oiled. (doesn't do anything for the cool sound, though) I would venture to say that in the 5 years Bob was hanging around the shop he didn't see one flat cam. If he did I can't remember. Right Bob? Did I miss anything?