350 mercruiser fuel economy

[Dr. Hook]

Well I got my info wrong, upon actually looking at the motor and working on it a bit I see it has a Rochester quadrajet 4 barrel carb.

This is my first season on the boat and time is limited so I'm still getting things sorted out. my fuel economy has been horrible, like 2 mpg at 30 mph.

I just cleaned the flame arrestor today so that may help. Picking away at other tune up stuff.

However I think the prop is the issue, it has a 14.25x21P aluminum prop with a big chip out of it and its in general rough shape. I can only get 4000 rpm so I think its too much prop for the boat.

Can you guys recommend a better prop? I want to go 4 blade aluminum, can't afford stainless right now. 4 blade because I like lift, control, and lower planing speeds, I couldn't care less about top speed.