150 Mercury 4 stroke on a 23 seacraft
 

https://www.mercurymarine.com/en/us/...units=imperial

This got me thinking : )

Those #'s are impressive for a boat that large

That you should strap 2 of these on a Shrimpco bracket ? ;)

At that point the hull has just gotten on plane thus the improved fuel economy. I'd like to see more motors tested on the sailfish hulls, closer to home... Tired of everybody testing on carolina skiffs and 19 foot tinnies.

My 23 has a top speed of approx 39mph (+/- 2mph with load/conditions) . . . 38.6 isn't too much of a loss. The conditions usually dictate your cruising speed anyways, so 95% of the time that is enough speed. The Merc 150 3.0L has almost as much displacement as the first generation yamaha 4 strokes 200 - 250hp (3.3L) and Honda 225/250hp (3.5L). It's only 4 cylinders, but it sure seems like it'll do the job.

Big, are you still running that 3L 250 efi? or did you go back to the old school lightweights?

Does anyone notice that mercury has removed the optimax
Test data for the 135 thru 175 2.5L engines.
The 21 Seacraft with a 150 opti had a 5 mpg cruise and
A top end in the low 40's looks like mercury did not want
People to compare old with new.

Redoing their website

Running the old 2.4's . . . saving the 250EFI for the 25.

Those are impressive figures! 3.5 MPG is unreal! My hull runs about 45mph but i rarely get up over 40 so who cares, run at 26mph sipping fuel, I have heard all good things about the new Merc 150 4 stroke too!