370 Aft Cabin speed?

At 3000-3400 rpm I'd expect 18-22mph if you plane it, cut it back and re-trim she'll cruise pretty nice. Sorry she's put away for winter, or I'd take here out and post a video for you.
 
TheBells13 said:
At 3000-3400 rpm I'd expect 18-22mph if you plane it, cut it back and re-trim she'll cruise pretty nice. Sorry she's put away for winter, or I'd take here out and post a video for you.
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Thanks for the info. I would be happy with that speed for this boat. Probably need to focus on the props to see how bad they are. Thanks, Mark
 
When I bought the boat it did 22 knots with 1/2 tanks of gas, half tank of water. Loaded up with full water and gas and gear it will do 18 knots. With dirty bottom it will do 14 knots. At 18 knots it turns at 3800 RPM and burns 44GPH. We normally cruise at 12 to 1400 RPM and burn 6GPH.
 
Northern, are those "top" speeds or cruise speeds?
 
northern said:
When I bought the boat it did 22 knots with 1/2 tanks of gas, half tank of water. Loaded up with full water and gas and gear it will do 18 knots. With dirty bottom it will do 14 knots. At 18 knots it turns at 3800 RPM and burns 44GPH. We normally cruise at 12 to 1400 RPM and burn 6GPH.
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Do you feel it's a waste to only cruise the boat at 12-1400 rpm? Is it just one of those things where you never expected the price of fuel to go this high and now you've had to adjust to compensate? I think I would fall asleep going that slow with such a big boat.

Doug
 
I agree, it could get boring. But you just can't argue with the MPG numbers that clip produces. Hey, if you're not in a hurrry, why not!?
 
There is some validity if you're not in a run. I just couldn't imagine going that slow. A 20 mile cruise will take you over 3 hours going that speed - one way! It would take all day to go out for a hamburger and back!

Doug
 
We go out for 2 to 3 months at a time. Have no need to get there quickly. When we worked we cruised at 12 knots as we would only go out for 2 to 3 weeks at a time.
Top speed was 22 knot when we got it.
Top speed now is 18 knots. We probably have added 3,000 pounds of gear, batteries, inverter, water maker, two 18 foot sea kayaks, trash compactor, large ice chest. When we start out we normally have 3 weeks worth of food and couple hundred pounds of wine beer, spirits and mix.
We do go 18 some times when we are in areas of high current or need to get out of bad weather. Going north you can run into 8 to 10 knot current in some areas.
Would be nice to cruise at higher speed some times but there are areas where fuel is 200 miles between stations. Never run out but have got to the point we had 50 gallons left out of 300. We tend to run the generator 3 hours a day that costs us 3 gallons a day so after 2 weeks and 200 miles we are getting close to empty.
 
douglee25 said:
Mark - What came of this over the winter?

Doug
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Doug, nothing new on the speed issue until I get it back in the water but I suspect my props are way out of wack. I haven't had them checked yet since I've been busy all winter trying to get the boat to the point that my wife doesn't start to cry when she sees it. I'm enjoying the process of bringing such a butchered and neglected boat back to its former glory and i finally got to the point where I'm working on the fun stuff (canvas, carpet, upholstery) so its going to start to come together soon. The props might have to wait until next year because I'm to cheap to pay someone to pull them off so it has to wait until I get around to it. Besides, I haven't had any good experiences when someone else touches my boat. Mark
 
Who says you can't do long-range cruising with a gas boa? Northern, I'm envious of your predicament! Happy Cruising!
 
Sea Ray Mark said:
Doug, nothing new on the speed issue until I get it back in the water but I suspect my props are way out of wack. I haven't had them checked yet since I've been busy all winter trying to get the boat to the point that my wife doesn't start to cry when she sees it. I'm enjoying the process of bringing such a butchered and neglected boat back to its former glory and i finally got to the point where I'm working on the fun stuff (canvas, carpet, upholstery) so its going to start to come together soon. The props might have to wait until next year because I'm to cheap to pay someone to pull them off so it has to wait until I get around to it. Besides, I haven't had any good experiences when someone else touches my boat. Mark
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Gotcha. If your speed is that far off, it may pay to have the props scanned soon than later to save some fuel cost.

Do you have any pics of your boat and the projects you're working on?

Doug
 
Rondds
You could go where we go or along the east coat up to Canada. Have friend with the same boat as you who wants to bring it to Mexico to Sea of Cortez.
Will be going north in May for month and a half as we have first two week of July committed for land things. With help I will post some pictures or creat a blog. Probably get just north of Vancouver Island. Not the big trip we normally do. As to fuel it still is the lowest cost of boating when you add up the other items like moorage, insurance and maintenance.
 
Just an update on my speed issue. Had the props done in the spring and ran down the Delaware Bay to Wildwood at about 17 knts and 3700 rpm which is better then it was but still a little to slow. Before I got to my marina I pushed it all the way up and was getting 5300 rpm WOT. I figured I need to have more pitch added to the props to bring down the WOT rpm which would also help my cruise speed. This week I had the bottom cleaned and took a cruise to Cape May and now she runs 15 kts at 3700 rpm and WOT is 4600. Not sure what's going on with this since the only thing I did was to load the boat up with a normal amount of gear during the summer. Didn't think the gear could slow it down that much. Does anyone have any specs from Sea Ray for this boat showing the performance numbers? I had a nice spec sheet for my Sundancer but not sure if they did this for all models.
 
Mark
Have you checked compression? Tune up? Your WOT is right but you should get better speed at 3700RPM.
 
Based on specs for your boat and mine you have a problem. I hit a log this spring and bent a prop. Had both rebuilt. It did not effect top speed but seemed to give me about 5% more speed at low RPM. You probably need a good tune up or have worn engines. As noted by others compression check is where to start. What is your estimated added weight for extra stuff in the boat. My boat at last haul out with 1/3 tank gas and 1/4 water was 15 Ton posted dry is 10 Ton by SeaRay. As I noted before I got top speed of 22 Knots before added things to the boat. If The engines ever die I will try to put ones with more HP. Until then I an stuck with 18 knots.
 
douglee25 said:
That's weird? How accruate are the tachs?

Doug
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Doug, I haven't had the techs checked but I'll probably need to do it now that I've gotten to the point that things aren't making sense. I can't assume they're correct with the info I've gathered now. Thanks, Mark
 
rondds said:
Mark
Have you checked compression? Tune up? Your WOT is right but you should get better speed at 3700RPM.
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Ron, I did all of that before I left Kent Narrows and everything was good after I replaced the broken rocker arm. I'll probably go back over all of the basics this winter. I was pretty sure after getting 5300 wot that a prop adjustment would get everything sorted out but now that it's only getting 4600 I'm not sure what direction to go regarding the props. I was hoping to pull them this winter and get them adjusted but maybe I'll double check all the other stuff first and have them done the following year if need be. I'm in no hurry to get it straightened out but it bothers me that it's not right. Thanks, Mark
 
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