That is quite a discussion over there. This all makes me glad my 153 has hydraulic lifters. My 270 has had a long good running life with the recommended lash, but the next time I'm in there I'll check it hot & cold.
Several years ago I had a noise that I was sure was in the valve train. I adjusted & re adjusted. I changed out the complete rocker setup. I checked valve height & seat pressure. I could never fix it. It ran fine but there was a noise that was definitely valve related. A few years later I changed from tube headers to cast Fentons. The noise went away. It ran better with the tube headers.
