www.iFourWinns.com

Do I read this table correct if I find out that the optimal rpm speed is 4500 since the range is 149 NM? (except of course for rmp's lower than 2000).

(Sorry for the badly copied table but I highlighted the connections NM, RPM and 172.)

Test Results (Printer Friendly Page)
Test Power: 1 x 300-hp MerCruiser 350 MPI Range
RPM MPH Knots Total GPH MPG NMPG Stat. Mile NM KM KPH LPH KPL dBA
650 3.4 2.9 1.0 3.22 2.80 246 214 396 5.47 3.8 1.37 69
1000 5.7 5.0 1.6 3.55 3.09 272 236 438 9.17 6.1 1.51 73
1500 6.7 5.8 2.6 2.56 2.23 196 170 315 10.78 9.8 1.09 76
2000 7.4 6.4 3.9 1.90 1.66 146 127 235 11.91 14.8 0.81 75
2500 8.5 7.4 6.4 1.33 1.16 102 89 164 13.68 24.2 0.57 79
3000 10.0 8.7 9.8 1.01 0.88 78 67 126 16.09 37.1 0.43 85
3500 19.6 17.0 10.5 1.87 1.62 143 124 230 31.54 39.7 0.8 85
4000 24.9 21.6 11.3 2.19 1.91 168 146 270 40.07 42.8 0.93 88
4500 32.9 28.6 14.7 2.24 1.95 172 149 277 52.95 55.6 0.95 89
5000 36.6 31.8 18.4 1.99 1.73 152 132 245 58.9 69.6 0.85 90
5600 38.3 33.3 22.8 1.68 1.46 129 112 208 61.64 86.3 0.71 91

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Four Winns 278 Vista (2006)

Just like the Boattest article says (where this V285 chart was taken from).......



If you choose to run a 350 Mag at 4500 rpm for extended periods to only get the longest NM range, your boating experience with your 06' 278 will be short lived. Max WOT range is 4800 to 5200 RPM, and at 4500 you are nearly at the WOT range. Your best fuel economy (which was your topic) is NOT at 4500 RPM.

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One of 4 Previous (Sold) Boats:
2000 Four Winns 268 Vista

Current Boat: 2004 Chaparral 235 ssi cuddy

Thanks for your input. So you agree that when it comes to getting the longest distance on the fuel in the tank it is better to run at 4500 rpm's (according to the table)?

But your comment means that with a wide open throttle, the "damage" to the engine is bigger than the savings on the fuel?

Regards, Rolf

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Four Winns 278 Vista (2006)

I'm confused by the table above. It shows data for RPMs at 5000 & 5600. Per the FW website, this power package should top out at WOT around 4800 RPM. If they did get to 5600 RPM, that's really howling for this type of motor in a boat. FYI, the table per the FW website shows an optimal run speed between 3000 & 3500 RPM.

I agree that the table shows an optimal run speed of 4500 RPM, I'm just not sure I trust the data. Get in the boat and find out where it tops out at at WOT. I would be surprised if it ran higher than 5000 RPM.

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2005 FW Horizon 250
8.1L VP DP