Hello everybody. I'm hoping to learn more about oil issues for my specific application since frequent internet searches and even an e-mail to an oil manufacturer returned mostly opinions and marketing. I'm running a small block Chevy with a roller cam. The engine has 13:1 compression and cranks 250 psi on the gauge. I run leaded 110 octane fuel. I had been using Mobil 1 High Mileage 10W30, thinking the higher ZDDP content would be helpful even if not totally necessary since I have a roller cam, but upon tearing the engine down for a freshening, I found evidence of corrosion inside the engine particularly on the connecting rods. The bottoms of the pistons had some crystalline material baked onto them. I did some internet research and found some discussion of issues with synthetic oil not being able to hold the lead halides formed during combustion of leaded fuel in suspension, and that the lead halides are corrosive and can lead to the type of damage I saw inside my engine. I e-mailed Mobil 1 hoping to get a response from an engineer, but all I got was a one liner from some marketing type who said was, "Sure, Mobil 1 will work fine in your application, go ahead and use it!" I do not know of any modern oils that are designed for use with highly leaded fuel except aviation oils, but I don't know anything about ashless dispersant oils and their use with a high compression racing engine. Any reasons why running Aeroshell 15W50 would be a terrible idea? Could I add a ZDDP additive to the Aeroshell oil to help with cylinder wear? What about the new Aeroshell Sport 4 stroke oil? Does anybody know what viscosity that oil is? Any other possible oils out there that might be able to handle the lead? Thanks! Joe