Took The Grady out yesterday do these numbers sound right?

jellyfish

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okay, got the 208 without a hard top out yesterday, filled her up and my buddy and me took her out to see what she could do. The 208 has a new 2009 Yamaha F 200 with a kicker 9.9 on the back of her. Top end New gauges was showing 60 RPM, 42 MPH AND 44 Knots with the current, vs the current was 41 to 42 knots. Does this sound about right to you Grady 208 owners? I was very impressed with the ride, even over some chop she was very dry. No trim Tabs on the boat. I have two batterys on each side and the and the kicker is mounted on the Stb side.
 

wanderer200

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Re: Took The Grady out yesterday do these numbers sound righ

jellyfish said:
New gauges was showing 60 RPM, 42 MPH AND 44 Knots with the current, vs the current was 41 to 42 knots. quote]

WOW! Watch out for a blow-over when you open her up to rpm! :wink:
 

Got Grady?

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By the sea by the sea by the beaut.......
So what does that mean to me?

The 228g I just picked up this weekend has a 200hp OX66 on the bracket with a 17 pitch stainless prop. I was running 5400 rpm at gps 42 mph which seemed right on the money compared to my last boat with the same motor and prop. That was the best I could do playing with the tabs and trim on the motor. Guess trim tabs do make a big difference because my last boat didnt have them but was a tad lighter.
 

Curmudgeon

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Don't bite, Jelly, they're attempting some humor because you listed the tach reading as shown (not every tach reads in thousands). Sounds to me as if you're about right with the prop IF those numbers were with engine trimmed out. A note about speed readings if taken from GPS, it reads speed over the ground and not actual surface speed if there's a current or wind.

I found trim tabs to be a wonderful addition to my T-22 ... :wink:
 

jellyfish

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Curmudgeon said:
Don't bite, Jelly, they're attempting some humor because you listed the tach reading as shown (not every tach reads in thousands). Sounds to me as if you're about right with the prop IF those numbers were with engine trimmed out. A note about speed readings if taken from GPS, it reads speed over the ground and not actual surface speed if there's a current or wind.

I found trim tabs to be a wonderful addition to my T-22 ... :wink:
Got ya, It was 5800 to 6000, but my tach only reads 58, 60. I took the knots speed from my Furuno 600L and did notice the GPS knot speed was less then the sounder speed. So what reading is right? I did have the engine trimmed up a little at 2. The prop I have is a 3 blade 19'.
 

jekyl

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Your GPS is the most accurate and as you noted you have KNOTS which is the way to go. It's got water underneath it when you are moving forward so it must be a boat!.

Ordinarily if your log or speedo was, accurate, then the MPH would always read MORE than your knots on the GPS.

Revs are great and that is to expected because of the different MAX rpm for a 4 stroke as compared to a 2 stroke.
 

jellyfish

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jekyl said:
Your GPS is the most accurate and as you noted you have KNOTS which is the way to go. It's got water underneath it when you are moving forward so it must be a boat!.

Ordinarily if your log or speedo was, accurate, then the MPH would always read MORE than your knots on the GPS.

Revs are great and that is to expected because of the different MAX rpm for a 4 stroke as compared to a 2 stroke.
Thanks, The MPH reading on the gauge were higher then the GPS knots reading on the Garmin but the MPH reading on the gauge was lower then the knots reading on my furuno sounder? Is that due to the Garmin GPS reading over land and the sounder reading over the water? If so what reading is the right reading? The Garmin GPS or the Furuno Sounder?
 

wahoo33417

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Jellyfish: Your numbers sound right. If you're topping out at 6,000 rpm with your typical load, then you're propped exactly right. And your speed sounds like it is just where it should be with an F200.

As a former 208 owner, I'll add that trim tabs are a good addition. I added mine several years after initial purchase and they made a good ride better.

Rob
 

jellyfish

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wahoo33417 said:
Jellyfish: Your numbers sound right. If you're topping out at 6,000 rpm with your typical load, then you're propped exactly right. And your speed sounds like it is just where it should be with an F200.

As a former 208 owner, I'll add that trim tabs are a good addition. I added mine several years after initial purchase and they made a good ride better.

Rob
Rob, Thanks ffor the feed back and thanks to everyone. I was almost full of fuel and had all the saftey stuff on the boat as well as my buddy. I was impressed with the ride. It was a dry ride. Not too much wind or chop on Saturday, so we shall see.
 

jekyl

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Is that due to the Garmin GPS reading over land and the sounder reading over the water? If so what reading is the right reading? The Garmin GPS or the Furuno Sounder?

That would be because the Furuno sounder is probably using a paddle wheel, attached to the transducer for it's speed calculation. (very basic) Whereas your GPS is getting it's reading from Satellites; hence much more accurate. A GPS reading over land or water is the same and is the definitive way to measure velocity.
 

jellyfish

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jekyl said:
Is that due to the Garmin GPS reading over land and the sounder reading over the water? If so what reading is the right reading? The Garmin GPS or the Furuno Sounder?

That would be because the Furuno sounder is probably using a paddle wheel, attached to the transducer for it's speed calculation. (very basic) Whereas your GPS is getting it's reading from Satellites; hence much more accurate. A GPS reading over land or water is the same and is the definitive way to measure velocity.
OKAY, The transducer is an Airman 66 with a paddle wheel. So I guess its my GPS reading and that was lower then the sounder. I will look at the reading on the GPS next time out and compare them. Thanks for the reply! sounds like you are happy with your new 4 strokes! Congrats.
 

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Before repowering my 208 Adventure, I had a 200hp Mercury Optimax outboard on the boat. The WOT speed was 42 mph under calm conditions with full fuel, 2 people, and the usual collection of equipment. Your boat speed is right on the mark. Repowering with a Mercury Verado 150hp, dropped the WOT speed to 38 mph.
 

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Jellyfish - you might pick up a little more top speed if you try trimming out further. I am always surprised at how far I can trim out the motor at faster speeds, and continue to pick up speed without cavitation. Try trimming out until the motor starts sounding funny and then trim back down just enough to get the noise back to normal. You may pickup some speed and efficiency. I do not enjoy running for any period of time at anywhere near WOT too much, but it is nice to see what the boat can do with the prop thats installed. Just watch you rpm.
 

jellyfish

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RICHNLE said:
Jellyfish - you might pick up a little more top speed if you try trimming out further. I am always surprised at how far I can trim out the motor at faster speeds, and continue to pick up speed without cavitation. Try trimming out until the motor starts sounding funny and then trim back down just enough to get the noise back to normal. You may pickup some speed and efficiency. I do not enjoy running for any period of time at anywhere near WOT too much, but it is nice to see what the boat can do with the prop thats installed. Just watch you rpm.
Thanks, I will play with her more on next trip out. The speed I got was enough for me so I am okay with what I got from her. I only had her at that speed for a very short time, the engine has 300 hours on her so shes getting broken in still. So far I am very happy with the F200 engine on that hull. Feels to me like the right engine for the 208.