Do These Numbers Sound Right?

Rick from Rocky Mount

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Had a chance to really open the new boat up this past weekend. I have a Volvo Penta V8 300hp with SS duo prop on my QCW 25 I/O. Initially, had 10 adults, 1/2 tank of gas and three fully packed coolers on board and opened it up full throttle at 5200 rpm to 40 MPH. Later, had 4 adults and full tank and opened it up at 5500 rpm to 42 MPH.

Boattest.com tested same engine on a 232 Cobalt runabout and it max out at 5500 rpm to 49 MPH, with single driver I believe. The Volvo website states that the max rpm for this motor is 5800.

I'm not a big prop guy, and I'm happy with my boat's performance as it seems to meet our needs nicely. Do these numbers sound right? Although not really interested in spending big $$ on another prop, would another prop get me much more? Just curious to see what some of you think? We typically like cruising around 25-30 MPH depending on the lake conditions. My wife gave me one of those looks like "really?" when I was WOT!
 
Also, took one of you guy's advice and tinkered/played with the Simrad and got it working correctly in the correct units. Above numbers were both by GPS and speedometer, which appear to be in synch for the time being. Thanks!
 
Unless you can get the dealer to try different prop sets, they can be pretty pricey.
 
I'd say your pretty close to where you should be. The first run is very heavy so 5200 is not bad, the second with four adults and 52? Gallons is close to max rpm so I'd leave well enough alone. Sounds like a sweet boat.
 
While it sounds like you have room to go down in pitch, my guess is that you won't pick up much in the way of speed. For the size and weight of your boat, I think 42 MPH is pretty good for that engine. I've got a GCW 2574 w/250 HP and top out at about 40 MPH @ 6500 RPM.

I get the same looks from my wife when approaching WOT and frankly, IMO going that fast is not as much fun on a pontoon given all the wind as compared to my bowrider.
 
Had a chance to really open the new boat up this past weekend. I have a Volvo Penta V8 300hp with SS duo prop on my QCW 25 I/O. Initially, had 10 adults, 1/2 tank of gas and three fully packed coolers on board and opened it up full throttle at 5200 rpm to 40 MPH. Later, had 4 adults and full tank and opened it up at 5500 rpm to 42 MPH.

Boattest.com tested same engine on a 232 Cobalt runabout and it max out at 5500 rpm to 49 MPH, with single driver I believe. The Volvo website states that the max rpm for this motor is 5800.

I'm not a big prop guy, and I'm happy with my boat's performance as it seems to meet our needs nicely. Do these numbers sound right? Although not really interested in spending big $$ on another prop, would another prop get me much more? Just curious to see what some of you think? We typically like cruising around 25-30 MPH depending on the lake conditions. My wife gave me one of those looks like "really?" when I was WOT!
I know that look!
 
The pontoon boats have more drag than a bowrider. Those numbers are close to max.
 
Thanks. That’s what I was hoping you guys would think. I’m happy with that performance. No need for me to go any faster. Certainly doesn’t feel like it’s dragging going full throttle.
 
You guys need to train your wife better. The faster I go, the louder my wife lets out the "Tim Allen" grunt.... "ough, ough, ough"!
 
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You guys need to train your wife better. The faster I go, the louder my wife lets out the "Tim Allen" grunt.... "ough, ough, ough"!

That's awesome!

While cruising around 4500rpm for several minutes, I usually get the "FLOOR IT!" call over the wind noise. Of course, this depends on water conditions, but still makes me smile every time!
 
My wife encouraged me to get 300HP motor because she enjoys going fast. I am lucky!
 
My former 2275RLCP had the Yamaha F250 3.3 litre with a 19 pitch prop. With clean toons, low fuel and 2 souls on board I hit 49mph. Once they got dirty that dropped to 42. Your Q is a LOT heavier just in empty weight alone not to mention that extra stuff so RPM aside, your top speed sounds right to me. Then again outboards don't directly compare to I/Os since you lose a little efficiency so here is another comparison that could help: My former Chaparral bow rider with the same engine (generation 5, I'm assuming yours too) got just a hair over 40. It felt like it was going faster but Chaparral's speedos are designed to feed the ego of the owner, not report an accurate speed. The boat said I was going 51 but the GPS said very low 40s.
 
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