NJ Saltwater Fisherman Forums
Boating => Boating General Discussions => Topic started by: Luna Sea 5 on December 31, 2007, 10:14:50 PM
-
When I bought my boat, I was thinking about how I wanted it powered. I decided to max it out to the 350hp max for the boat. I had to do that with twin 175's.
Now that they make a single 350hp, I was wondering what the difference would be to have a single or twin engines with the same hp.
I know the basic. Single = better gas milage, twin = more power and control, but HOW ABOUT TOP SPEEP and anything else.
-
Nick
You'll get better control with the twins as well as better fuel efficiency
-
better fuel with the twins?.. didn't know that.. how about top speed
-
Single 350 will be faster then twin 175. Twin 175 is not true 350 horsepower. Forget the exact formula, but should be closer to 280-300hp (equivelant). A single 350 will be lighter then tin 175's and the drag of the engine will be less with a single prop/lu in the water then duals.
-
That makes sense, but giving all the pro's and con's between the 2 scenarios, which would most people prefer.
-
For ANY off shore trips, most guys prefer the safety of twins. If one engine fails you can always limp in with the other.
I do MOST of my fishing within ten miles from the shore and personally prefer the less costly single engine. Less maintenance, winterizing, etc.
-
Good article on twins vs single in the Yammie world:
http://www.trailerboats.com/output.cfm?id=1255843§ionid=313
Sea tow is MUCH cheaper (as is a kicker) then dual engines.
P.S. single engine is usally more fuel efficient then duals. Forgot to add that in my Original post.
-
Good article on twins vs single in the Yammie world:
http://www.trailerboats.com/output.cfm?id=1255843§ionid=313
Sea tow is MUCH cheaper (as is a kicker) then dual engines.
P.S. single engine is usally more fuel efficient then duals. Forgot to add that in my Original post.
Capt. Bob stated above that the better fuel efficient set up is with the dual engines. 5hrug
-
This is true. But when you are 35 or more miles off shore and can't reach out to sea tow and only slightly making headway with your kicker, you will be kicking youself in the a$$ for not going with the twins. If you are into some bad seas, the kicker won't be much of a help either. And that longggggggggggg wait for seatow...
But then again, if you are going that far off, best to do the buddy system and pair up with another boat if possible. t^
Still, as I said before, I only prefer a single engine for my needs.
-
Better fuel efficiency with a single!!!
Faster out of the hole with the twins!
Better control with the twins!
MORE MONEY WITH THE TWINS!
I Still perfer the twins for offshore and peace of mind.
2008 gas prices will say other wise!!!
-
Mike, great find... good info on that website.. I guess nothing is guaranteed as the statement below states..
Performance-wise, our testing over the years has generally shown that if horsepower is the same, a larger single engine will be faster than two smaller engines because the single-engine boat is lighter and, with only one prop, it has less drag. This is not always the case, however. Fuel economy is another area where a large single sometimes fares better — but, again, not always.
I noticed on the size boat I have, I don't loose any top speed if I drive by myself or I have 2 others with me, the the minor difference in weight between the twins or the big single shouldn't mean much. Then with the fuel, to get to the same speed, one engine helps the other so neither are being overworked.. I guess everything is a matter of preference.
-
This is a very interesting topic since most people in the boat market want to power there boat to preference. What I noticed with a single and a twin is... With a single engine, the weight of equipment and weight of 3 guys on the boat will alter the speed lower quite a bit. With the double, I don't seen any difference in top speed with a full load or by myself..
-
The single vs twin propeller/engine propulsion question has several interesting ways to be considered. Let's look at them:
--Twin propellers (and lower units) have more drag than a single. It takes more horsepower to drag two propellers along than one. Efficiency favors a single.
--The propellers on twin engines operate in less aerated water (because it is not coming off the keel or deepest part of the hull) and may be more efficient.
--The crankshaft speed of twin engines at cruise is normally much lower than a single engine. For example, consider a pair of 150-HP engines compared to a single 225-HP engine. At cruise the twins are probably going to running about 3,000-RPM. The same boat with a single 225-HP engine is going to be turning about 4,000 RPM. This is very significant.
A 150-HP engine turning 3000-RPM is operating right at its "sweet spot" for fuel efficiency, while a 225-HP engine running faster at 4,000-RPM is beyond the "sweet spot" and is not running at optimum fuel economy. This is where all the difference in fuel efficiency probably comes from.
If you take engines of similar technology and run them at the same engine speed, they should all be operating at about the same fuel efficiency. But when you compare them at different engine speeds, they get different fuel efficiency.
Engine mounting is also a factor, mounting an engine on the Transum as opposed to mounting on an engine bracket, also the hull design, weight of boat, rise of hull, trim-tab position, diamiter and pitch of the propeller all come into play...........
I can only give an example, I run a 225 Yamaha 2 stroke on a 24' Grady, my budy has two 115 hp 2 stroke Yami's on a 24' Grady.....he is getting better fuel effeciancy than me.....the only differance in our boats is that he has an engine platform and I an transum mounted
I have talked about this a lot with my Yammi mechanic, have called Grady and Parker Boats, all concer that the twins are more fuel efficent than the single on the type of boat inquired about 24 or 26' Grady, 25' Parker
Just my Humble opinion......as with anything everybody will have their point of view.
I can only say that the "Donna Marie II" will be a 25' Parker or 26' Grady with Twin 115/150 4 Stroke Yammi's TT^ TT^
-
I can only give an example, I run a 225 Yamaha 2 stroke on a 24' Grady, my budy has two 115 hp 2 stroke Yami's on a 24' Grady.....he is getting better fuel effeciancy than me.....
which boat has a higher top end speed, the single 225 or the twin 115's.
-
single, but not by much
-
very interesting and very good topic... especially for people who are in the market with the boats show here... If you in the market of buying a boat, make sure you get the facts about everything before you commit with the $$$$ factor..
-
whs
-
In todays used market especially. Let the buyer beware, if something seems to good to be true there probably is something amiss, and time to move on.
-
Don't forget to factor in maintenance. You double the cost with two engines although some of the larger singles may cost more than one single but certainly not double. You also have to assume if you hit something two props and lower units are involved. Sea Tow or Tow Boat are a lot cheaper than a second engine if you are looking for security and they will tow you to your home port. Just some additional thoughts for consideration.
Bob
-
slt Good food for thought...
-
It all makes sence... I'm just amazed with the new single engines that are rated 350 hp.
-
Any experience with Sea Tow Bob rofla
Also make sure you have a service agreement with Sea Tow or Boat US so you don't have to pay $1k for them to come and get you or dive under you) chrz
-
It sucks being towed in.. Its the longest ride ever. I remember getting stuck on the water and while we were waiting for Boat US to come, I started fishing. My father was like WTF, don't you care we are stuck. I said, yes I care, but what the hell else are we going to do out here...
-
That was last Friday.
-
did you guys get towed? I thought the diver fixed the problem...
-
The most important thing to consider when chosing single or twin engines....is what you are ging t be utilizing the boat for and what you expect............
yeah you can rely on a tow service, but if you are way off shore, or they are far from you, or you are in a situation, that second engine is real handy.
As far as Maintenance, is is not that much more to keep up a second engine, unless you have some else do it for you...
you can play what if games all day on the subject, everybody will have their opinion....having run bth ways I prefer a twin setup TT^
-
mboy- Have had Sea Tow for 15 years, used them once when I had a dead batteries. They came out in 30 minutes. know several others who used them and TowBoat. Everyone was happy with the service around Raritan Bay but those that had to pay were sorry they had not spent the money up front. Sea Tow also has trailer towing coverage while you are on the road towing. Not sure about TB. Costs me $150 this year but since I am out several times a week I fish at ease should I have a problem or hit something or wrap a rope on prop!
-
i also reccomend having the unlimited tow package.
-
Wouldn't leave the dock without it! t^
-
It sucks being towed in.. Its the longest ride ever.
LOL. I had to be towed once on my old boat. Allll the way through the Manasquan River. You feel like everyone from all the other boats are pointing and laughing. What was funny the one time I got towed was that another TowBoat US boat towing another guy was going in the opposite direction. The guy and I had a laugh waving to each other sitting in our disabled boats.
-
thats OK.. let them laugh.... especially if they are laughing from the beach and jetties... REMEMBER.. your in a BOAT...
-
Just another thought on the multi-engines vs single-- yes if you scuff a ring or throw a rod or have some other mechanical problem duals are (expensive) insurance, but they likely won't help at all if, say, you have a fuel-related problem and are drawing from one tank.... now you got 2 mucked up engines and still need a tow (or some of them filthy oars.)
-
The average problem one may have on the water it too unpredictable.. I have 2 engines, not only for security, but for STATUS QUO... ;D.. just kidding... Mosty for power it ocean water when you have to ride and surf the waves sometimes. IT DOESN'T MEAN I WILL NEVER NEED OR USE SEA TOW..
-
I would no more venture out with out my Seatow membership than I would without my Electronics.............
one and only time I used them was on my previous boat when my engine died at my dock, as none of my buddies were around, gave them (Sea tow) a shout and they towed me up river to my mechanic........only cost me $30 for the tip chrz
Being on the water is not like being in a car, ya can't pull over and wait for Mom or Dad to come get you t^
-
hmmm .. SeaTow or TowBoat US? dont't want to be a hijacker so I'll make another thread...
-
answered...