prop/performance numbers for 2120 with F225

[rloomis]

got Barely Legal WOT late Saturday morning during slack tide with <1ft swells and <5kt winds using Yamaha 15x17 black stainless steel prop and she was able to hit 5800 rpm and 41mph. Just myself on board but loaded down with a full gas tank, full 48gal bait tank, fishing gear, ice and salt water slurry in the cooler (and 1 sandbass). With tabs and motor trimmed down I can gun it to about 3800rpm and she comes on plane in less than 5 seconds .
I'm going to try spinning a 15 1/4 x 15 Saltwater Series II next and see how it compares.

 

[susqking]

Were you trimmed up at WOT? I think with the smaller prop you will be turning 6200 rpms or better.

 

[ABRIG005]

those are suite similar number with the f150 with 2 people and 3/4 tank of fuel.

hey how hard is it to install the 12V outlets?

thanks anthony.

 

[rloomis]

Had another day with some flat conditions to let me go WOT and filled in more data on the performance curve. Here's a shot of the updated spreadsheet with a chart of speed/fuel vs RPM. The second chart shows just the MPG data. Interesting how the MPG decreases with RPM in little node cycles showing best efficiency around 4400, then with lesser peaks at 5200 and again at 5900.

This is with the same black SS yamaha 15x17 prop as before. Most of my cruising is in the 3800 to 4200 RPM range because of swell and chop not making it too easy to run faster than in the low 20's MPH range.

Ran with just myself on board with about 80% full gas tank, 48gal bait tank filled 1/2 way, and large cooler with water ice and fish. I was able to get to 5900RPM and top speed about 42MPH (SOG measured by GPS). My best MPG was about 2.52 MPG at around 4400-4500RPM which was moving around 28-30MPH.

I'm still thinking a change from the black steel to the Salt Water Series II 15 1/4 x 15 is worth a try. Dropping from 17 to 15 pitch with the cupped blades might get me a little better bite in the water and be able to get me an extra 200RPM to cruise more efficiently closer to the 4400 RPM spot without having to go 30MPH to do it.

 

[rloomis]

those are suite similar number with the f150 with 2 people and 3/4 tank of fuel.

hey how hard is it to install the 12V outlets?

thanks anthony.

Installing the 12V outlets was super easy for me -- the electronics installer did it for me and didn't charge any extra! 8)

If you have to do it yourself, it just takes a circle cutter and a few self tapping screws. The wiring is just 2 wires: +12V and GND with either an in-line fuse or connect them to terminals on a fused bus-bar.