Always found things like this fascinating. Great to hear real world stuff like this. I can and have seen the benefits of these things over paper elements filters. But can’t imagine any benefit over what is essentially very similar, with the usual flame arrestor mesh on most mercruiser. Have it in my head that the 7.4 mpi variants might have slightly less direct breathing ability perhaps? Not sure. Even so…I think to see any noticeable difference, you’d need some way of getting a flow of externally sourced colder air fed to things. Often thought about how I might manage that on my own boat. Probably silly.If this helps any and for what it’s worth, From personal experience on running several both stock and Merc High performance blue engines boats at wide open throttle while under way and closely watching the RPM digital readings on a scan tool of some engine models while chasing other issues, there wasn’t a single number change in RPM or even MPH from simply removing the stock flame arrestor and reinstalling it at speed several times in a row. Honestly saw no benefit in spending extra money for nothing seemed gained.
It is the sticker that comes with it when adhered to the windshield that makes the boat fasterIf this helps any and for what it’s worth, From personal experience on running several both stock and Merc High performance blue engines boats at wide open throttle while under way and closely watching the RPM digital readings on a scan tool of some engine models while chasing other issues, there wasn’t a single number change in RPM or even MPH from simply removing the stock flame arrestor and reinstalling it at speed several times in a row. Honestly saw no benefit in spending extra money for nothing seemed gained.
