318 MAX fuel economy builds?

OK, a combination of too much heat hitting the plenum floor, generous EGR (perhaps), and lots of heavy stuff coming through the PCV port. It helps to diagnose the cause of issues and not just band-aid them over. Would less heat in the cross-over have hit the sweet spot? Was there excessive blow-by where a PCV catch can would have resolved it? Could a better carburetor (look at the praise the T-Quad gets on this site) have made things better?? The outcome was obvious, but I'm curious about the diagnosis and fix.