Looking at a 1986 4207

[buster53]

I used to have a 3807 with 454’s (330 hp). It was a dog and sucked down fuel big time. I can’t believe that Carver would even offer the 4207 with gas engines.
Anyway, if running hull speed is your primary usage, you will be fine. We ran our 3807 at hull speed 95% of the time mainly to hold fuel costs down and even then, I believe we only got about 1 mpg.

[waybomb]

I had a 1989 4207 with had engines. That's why I sold it. A beautiful boat. If i could find one with 450hp diesels, I'd probably buy it, even if it needed a full renew.
Those had engines are almost dangerous in that boat; nowhere near enough power of you get caught in any kind of weather or seas.
River running, probably fine. Small inland lake, probably fine.
Great lake or coastal crossing, no go.