Performance (rpm, speed, mpg) report for my Tidewater 21 Yamaha F150

[Onewolf]

I recently upgraded the engine gauges on my Tidewater 21 Bay from the Yamaha analog gauges to the square command link gauges. I did some performance testing on the river today just to get a feel for the fuel economy at various speeds. The command link speedometer seems vary accurate (less then 1 mph off the GPS speed) once you get above idle speed.

Load: fairly light, 1 person, full fuel, normal gear, 1 cooler with ice/drinks
Prop: Michigan Apollo 15.25" x 17" (I tried a Yamaha Reliance but I didn't like the performance compared to the Apollo)
Air temp 85, water temp 82
At 2800 RPM the boat stays easily on plane with no trim tabs
Speeds are in MPH

RPM ------ Speed ------ MPG
2800 ------ 19 -------- 5.3
3000 ------ 21 -------- 5.4
3500 ------ 26 -------- 5.3
4000 ------ 31 -------- 4.8
4500 ------ 35 -------- 4.3
4800 ------ 37 -------- 4.0
5000 ------ 39 -------- 3.9
6000 ------ 45 -------- 3.0

[Joe]

That's pretty strong.

I do love the F150---great power and excellent economy!

[jets]

How hard was it to replace the gauges?
Good report!

[Onewolf]

Replacing the gauges was relatively simple. They mount in the same diameter hole as the Yamaha analog (and older 'digital' gauges). You just have to run the main bus cable from the engine to the console and mount a network 'hub' in the console and run short pigtail cables from the net hub to the speedo/tach gauges.

Doug

[jets]

Thanks!