@moper i just had the same thought "what about running the Magum Heads on the 273" but it just leads to problems with valve size vs bore and also rocker oiling thru the pushrods will be the next issue...
No issue on the oiling part. I'd think bore notches would be fine too although I never tried. The Magnum is a much better head than the LA 318, and you're already talking about redoing and porting those. Up to you but that would be my path unless and until there was no notch that would work.
