Looks like Cat is going after the repower market for smaller HP older boats. They claim the new 7.1 is perfect to replace 3208's or "two stokes". Based on the hp, I'd say that means up to 8v71's could be replaced with these. And notice how much emphasis they put on how quiet they are. Seems like they are giving a real sales pitch to replace your DD's.

https://www.cat.com/en_US/articles/c...n-engines.html