Tim, don't you want to try and get those RPMs up? That thing should turn 5500RPM, no?

I agree I think you are missing the powerband of your 540's. 5000-5500. I spun my mistress to 5650. to run 78-79. The Top Gun spun 5700 RPMS as well.

Yep, I haven't seen anything over 5100 RPM in mine, and would like it to get up to about 6K when setup properly. My peak power isn't until 5750-5800.....

I just mainly been running what it came with, I need to play with the propping if I feel like it, cruise is nice, I may searxch for some to try end of season here to see what 53-5500 does, I wish I knew actual power of these engines and range.

What pitch are your 3 blades tim?

What diameter?

3 blades are 16.5X27. drives 1.58 ratio

Not sure any top end gain would be worth losing cruise speed at this point, I had a great season cruising 55-60 mph and just enjoying the boat, knowing the drives will hold up when it got ugly out is even a better feeling, torn on messing with what is working......

Yeah, I hear you on the cruise. Maybe try to acquire another "top end" set over the winter? If I recall, a 1" drop in diameter should yield +300-500 RPM? But 15.5" seems awfully small for your boat. Maybe try 24-25 pitch?

I think id prob leave it be. I doubt bigger diameter will help him with his drives being deep.