I've always used Rotella T oil, never heard of Rimula until you posted that name. I did a little research and it looks like Rotella is marketed to us regular users and Rimula goes to fleets primarily. Even with Rotella I like to dump a can of something like Comp Cam lube in, just because. It is cheap insurance (lots cheaper than cams and lifters).

There has also been speculation that cams today aren't as wear resistant as they were years ago. I don't know why that would be the case, but something I have heard............who knows.

I did run Mobil One synthetic in the 302 in my 27 for a while. I noticed a little more hp feel and the temp went down 10 degrees or so. But when I tore that motor down a few years later the cam and lifters didn't look so hot. Rough edges on the lobes and the lifters were concaved a little. Not sure that was the cause, but maybe.

Don