“ Fast boats” then and now ……
 

Remembering when an Evinrude 100-125 considered a BIG outboard and powered assorted run abouts 25-30 mph.

Then the Merc tower of power 140/150 the biggest.
Then the 200 hp and it was a new era.

Now …200 is average outboard, as 300hp bit of a standard outboard,
with 350, 400, 450 and the monster being 600 hp Yami.

Adding ,….and 50-55 mph boats also very typical .
Not till over 65 mph considered very fast for good size center consoles with twins or trips