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Outboard Vs Inboard

G

Geewest

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I was told from a sales person at a local marina that the performance on a outboard is WAY better than a inboard

I.E the V8 350

This is a quote from him "we dont order or sell any inboards because the performance on a outboard blows away the V8"

He said if you throw a 200 or 250 outboard on a 25 foot bennington the zero to top speed is the same with the outboard and the fuel consumption with the outboard is about 1/2 that of a V8. Is this true?

The "small engine envy " thread had me re thinking my purchace of a V8 inboard.

We love the look of a inboard bennington. I love the swim deck you get with the inboard. We also love the ability to haul across the lake at over 40+ mph. We dont love the gas bill a 65 gallon tank can present when the gauge hits "E".

Just wondering what the facts are when it comes to pros and cons to a inboard VS a Large outboard

P.S what is the. Largest outboard one should or could get on a 25 foot bennington Q
 
In terms of the stock Bennington line, outboards are faster than inboards when you try to compare apples to apples.

Would a 350hp outboard be faster than a 425hp inboard? My marina's owner says so, and although I've not seen any good match-up to confirm this, he's been running that marina for decades.

On the other hand, you can buy an aftermarket supercharger for your inboard. The 377" Mercruiser is a bit of an under-the-radar monster with forced induction.

But, you mentioned gas consumption, so... Frankly a 25" Tri-Toon with a 250hp outboard is going to be a hard "overall" combo to beat.

But, having ridden/driven a 350hp Yamaha Q.... The biggest Yamaha outboard you can get... It's kind of sweet.

In THEORY you could go with an aftermarket motor like the Seven Marine 557, which is a supercharged Caddy CTS-V engine with over 550hp. Unfortunately, the highest rating that Bennington gives to their Outboard boats is 350.

Oh sure, you can take your boat to Seven Marine LLC and have them re-certify it, but I'm pretty sure that turns your Bennington warranty into a cocktail napkin. ;)

But here's the important part.

No disrespect intended, but lets face it...

If you're buying a Q, the price of gas is an ANNOYANCE, not a dealbreaker.

If you get the 320hp inboard it WON'T be as fast as the 350hp outboard, and that's not just a 30hp difference issue.

However, the inboards are fundamentally automotive cores with a marine life support system, which means they more amenable to poking along at 3000rpm, which will STILL get you a nice cruising speed. The difference is that they have an automotive weight reciprocating assembly inside, which carries MUCH more inertia than the ultralight outboard assemblies.

There's nothing wrong with either, mind you... Both are good solid engines that will last a long time if you take care of them.

If you're envisioning a family fun boat, as opposed to a bachelor's toy, I would SUGGEST the I/O version of the Q.

But either way, you'll need a plastic surgeon to wipe the grin off your face.
 
Ericscher, I want to buy you a 12 pack and fill up your Benny with gas if you'll let me hang with you for a day. I can learn more in 5 minutes, reading your posts than I can spending a year "talking to know it alls" at my marina.
 
spinzone said:
Ericscher, I want to buy you a 12 pack and fill up your Benny with gas if you'll let me hang with you for a day. I can learn more in 5 minutes, reading your posts than I can spending a year "talking to know it alls" at my marina.
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Me too!
 
I think both have their advantages. I have gone from 3 straight inboard ski boats to a 250 HP Yamaha outboard on my Bennington R series. I think the inboard has a cleaner look with that swim platform. Kids can jump right off the back with no outboard in the way. That beige said, a large outboard is impressive in looks and performance. A 250 outboard is going to provide more performance than a 250 hp inboard in my opinion. Also, the stern area on the Q series is very spacious regardless of engine choices.
 
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spinzone said:
Ericscher, I want to buy you a 12 pack and fill up your Benny with gas if you'll let me hang with you for a day. I can learn more in 5 minutes, reading your posts than I can spending a year "talking to know it alls" at my marina.
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I'm TELLING you, I don't actually know that much!
 
ericscher said:
I'm TELLING you, I don't actually know that much!
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Maybe not. But, if your not dazzling with brilliance, then your baffling with ummm . . . bull excretement. Seriously, you do a good job of explaining things technical.

A lot of the time, I look at a post and think, "lets let Eric handle this one just to see what his take is on this."
 
"If you're buying a Q, the price of gas is an ANNOYANCE, not a dealbreaker"

I have seen the price of the Q as little as $5-8K diff. IMO that's not that much money in the overall purchace of the boat over the lifetime for getting what you want. And just because you can afford the gas dosen't mean you feel like wasting it. If I could get the same performance out of a Outboard that I could get with a V8 IO and the Gas consumption would be in 1/2 I would seriously consider it. I don't like the look of a outboard and the loss of the swim deck but I do like the IDEA that you might be able to burn less gas and doing or getting the same thing just by making a simple choice at your initial purchace.

The Idea of the question and or the thread was to try and put number on Gas consumption on a V8 IO VS a Outboard.

The question still remains. It would be nice to see hard numbers Speed Vs GPH on specific bennington drive options
 
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Geewest said:
"If you're buying a Q, the price of gas is an ANNOYANCE, not a dealbreaker"

I have seen the price of the Q as little as $5-8K diff. IMO that's not that much money in the overall purchace of the boat over the lifetime for getting what you want. And just because you can afford the gas dosen't mean you feel like wasting it.
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I was referring to the overall cost of the boat, not the cost of an upgrade from a different model. And certainly a person doesn't get to be in a position to BUY a top of the line Pontoon by being frivolous with money. So if you felt that I was a bit too flippant on the subject, please accept my apology.

Having said that, I stand by my viewpoint that, provided you can afford it in the first place, fuel consumption should not be the primary concern when making these decisions.

Will it be painful to fill that tank? Heck, it's painful to go to the MOVIES these days, if you hit the snack bar.

OK, numbers...

You understand that your mileage may vary...?

With the I/O you're going to get a burn rate of around 22.5gph at top speed, which should be in the mid-40's at around 5000rpm. At around half that rpm, which is about 20mph you'll burn around 6gph, but it starts going up rapidly from there. Push your speed into the mid-20's and you'll be at 10gph+ real quickly.

Understand, that's from a different pontoon boat manufacturer, but in a 25 foot model with basically the same engine.

As for the outboard, this is from a test drive article here:

Test Drive

Test Engine: Yamaha 350 4-stroke

Test Load: People (190 lb.); Fuel (25 gal.)

Top Speed: 47.4 mph @ 6,000 rpm

Time to 20 mph: 3.7 sec.

Time to 30 mph: 5.8 sec.

Time to 40 mph: 8.8 sec.

Most Economical Speed: 25 mph @ 3,200 rpm, 8.5 gph

KEEP SOMETHING IN MIND THOUGH...

Boats aren't like cars when it comes to judging mileage. You and your twin brother could go out on the lake in identical boats, spend the day having fun and come back to the dock only to discover that you had much different burn rates. Little things make a huge difference... a few hundred RPM that you aren't even consciously aware of can be the difference between 5gph and 10gph.

This is a big part of the reason why I believe that while fuel consumption should be an important issue, it should not be the MOST important.

Correct me if I'm wrong, but your gut level preference is the I/O. You're just worried about the extra fuel burn outweighing that preference.

Think of it this way...

You're going to feel pain at the pump WHICHEVER engine you buy. But it will be fairly short lived. On the other hand, you'll spend hours out on the water USING the boat. For hours. If you buy an outboard when you really want an I/O (or vice versa) it will potentially annoy you for HOURS instead of minutes.

Either way, I envy you. It's a sweet boat regardless of the power you choose. Good luck.
 
You were not being flippant on the subject in any way, No apology needed. I totaly understood your comment and it's a very common one. Example you will see a person with a offshore boat roll threw with 2 Giant Motors rumbling past. You might ask or wonder how much gas that thing burns? Common answer "if you have to ask or your worryed about gas then you cant afford it"

You did a good job answering my question. So you think a V8 IO at let's say 20 MPH burns threw 10 GPH and a Outboard is like 8 GPH. I know these are rough numbers but they are no where near the 1/2 gas consumption like what I was being lead to believe. And if the numbers were like this all the way threw the test i would say the outboard dosen't make sence for me

Now when you do a Apples to Apples comparson based only on performance. "NOT HP"

Example you said a 320 HP V8 is gonna get out performed by a 350 HP Outboard Ok let's back it down.

Would a 200 or 250 Hp outboard be equal with a 350 V8 IO?? and if so then what would be the GPH rate of a 200 HP out board VS the V8?
 
You are seeking precision in an area where there is little or any to be found. I'm sorry, but that's the nature of the beast.

Generally speaking an outboard will be faster and more fuel efficient than an inboard of roughly equal power.

How much more fuel efficient is a question with an answer so variable as to not have a meaningful answer. All anyone can do is to try to compare the experiences of others with as similar a package as possible.
 
Sounds to me like you would really prefer the I/O. Rarely have I been disappointed when I have spent more to get what I really wanted when choosing between two items. Get the one you know you will be happy with and don't compromise if you don't have to.
 
I went from a 2002 2580RL with a 115 Yam 4S to a 2010 2575RL with a 350 MAG

I moved to a private lake that does not allow outboards of any kind, so I had to go with an i/o

I was very happy with my yammy and 2580RL, but...

Pros for yam 115--VERY easy on fuel, esp at lower speeds and loads compared to the 350 MAG

Yam was quieter, esp at idle

Pros for 350 mag i/o

Power is heads and shoulders above the 115, as expected

the 350mag seems to be quieter at hi-speed, 3/4 throttle+

The boat looks much cleaner overall without the the outboard sticking out, clean swim platform huge plus over outboard

Max speed with yam was 22mph, for 350 is almost 43mph

Summary--i/o if $ is not a concern, overall fuel use seems about 2x over the yam
 
Good info Ionize. Isn't it interesting that the lake will not allow outboards but you can have a big honking V-8 I/O. My last inboard was much louder than my new 4 stroke yamaha. Got a feeling it is because of the older 2 stroke motors that were loud and smokey. Hope you will post some pictures of your toon in the Gallery section for all to enjoy.
 
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What I have heard is that a 250 outboard will perform about equal to 350 mag I/O. You can get fuel consumption figures on the Yamaha outboard web site in the performance bulletins. I went with a outboard after only owning I/Os because I wanted to extend my boating season. With an I/O I had to winterize in Oct for fear off having a hard freeze and cracking a block. With the outboard I can wait until Nov or Dec also I can go out anytime during the winter or spring and not have to worry about rewinterizing.
 
We recently took delivery of a new 2550 RCL w tritoons and ESP package and 300 HP Yamaha.

It will reach 47 mph w one person aboard and full tank of fuel. It burns 24 gph at full throttle.

With 9 passengers on board and bimini up the top speed degrades to 42 mph.

My favorite cruise speed yields a 6 gph fuel burn, I believe it's about 3500 rpm and about 28 mph.

We recently were cruising along when a South Bay IO came up along us. I could not let him pass us up without pushing the throttle to it's limit... We pulled ahead and slowly started to walk away. I am guessing he was going about 40 mph and we were showing 42 with our load of 9 passengers. The other captain was not that happy...kept staring and squinting at us. I don't know what motor he had.

We looked at the 350 HP V-8 Yamaha outboard when we were ordering the boat (the max engine for the boat). But the additional 200 pounds of the V-8 motor seemed to me to offset most of the benefit of the higher output. Plus I think it was nearly $7k more than the 300 HP unit.

So far we are very happy with the Yammie. It's very quiet, smoke free, and has started every time on first try. We are on a shallow lake, so an outboard tends to be easier to manage. That said I will certainly say that the IO models look SWEET with the full deck across the back.

My brother has a saying, you only pay for something once. So get what you really want, especially if you are going to own and enjoy it for many years.

Mahalo

Spock Out
 
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I can't help you with the fuel efficiency numbers on the IO, but I can give them to you on my outboard.

Being a bit of a tech geek, I added GPS and a mercmonitor system to my 2010 2550 RCW. I know the data it is feeding me is accurate. I have the 250 verado. I get right at 3mpg when running 18, 1.8mpg in the low 30's, and have a top speed of 44mph(don't remember the mpg at that). I feel there is more in it as I am not happy with my current motor height and prop selection. Unfortunately, the local verado guru closed shop and I have to find some one else to help me with changing setups and offering me props to test with. :( Currently running with the motor in the second hole from top and turning a four blade 15p stainless prop. I want to raise the engine another hole, and try a three blade 17p prop next.

I'm heading out on the lake shortly. I'll jot down some notes for various rpm/speed/and fuel burn rates and post them up later.
 
ImaPoser said:
I can't help you with the fuel efficiency numbers on the IO, but I can give them to you on my outboard.

Being a bit of a tech geek, I added GPS and a mercmonitor system to my 2010 2550 RCW. I know the data it is feeding me is accurate. I have the 250 verado. I get right at 3mpg when running 18, 1.8mpg in the low 30's, and have a top speed of 44mph(don't remember the mpg at that). I feel there is more in it as I am not happy with my current motor height and prop selection. Unfortunately, the local verado guru closed shop and I have to find some one else to help me with changing setups and offering me props to test with. :( Currently running with the motor in the second hole from top and turning a four blade 15p stainless prop. I want to raise the engine another hole, and try a three blade 17p prop next.

I'm heading out on the lake shortly. I'll jot down some notes for various rpm/speed/and fuel burn rates and post them up later.
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I have the Verado 250 Pro, on a 2574 GlI, and with a 15 Enertia 3 blade, I am running 47 mph on GPS, at 6500 rpm with 3 on board. I have a 16" Enertia on order to drop the rpm a bit, and maybe gain another mph. Have only been looking at mpg info, 1.9 mpg at 47 mph, 3.5 at 35 mph. I must say I am pleased with the boats performance. As far as I/O's, its been my experience of 40 some years of boating, that it always takes alot more I/O HP to match an outboards power. I know part of it is weight, a V8 I/O is about 400 lbs heavier than a 250 HP Verado. (Not to mention how hard an I/O pontoon is to service). As far as the kids jumping off the swim deck, don't forget there is still a lower unit and prop hanging out there.
 
LT1GMC said:
I have the Verado 250 Pro, on a 2574 GlI, and with a 15 Enertia 3 blade, I am running 47 mph on GPS, at 6500 rpm with 3 on board. I have a 16" Enertia on order to drop the rpm a bit, and maybe gain another mph. Have only been looking at mpg info, 1.9 mpg at 47 mph, 3.5 at 35 mph. I must say I am pleased with the boats performance. As far as I/O's, its been my experience of 40 some years of boating, that it always takes alot more I/O HP to match an outboards power. I know part of it is weight, a V8 I/O is about 400 lbs heavier than a 250 HP Verado. (Not to mention how hard an I/O pontoon is to service). As far as the kids jumping off the swim deck, don't forget there is still a lower unit and prop hanging out there.
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Thanks for the comparison info. I'm still playing with engine height. What hole is your motor mounted in?
 
I didn't have time to read every comment here but I don't think anyone mentioned the difference in sound. I bought an outboard because they are so much quieter!!! I/O's are nice from an esthetics stand point but you can hardly have a conversation when your cruising. We can have a normal conversation at WOT. Anyway, just another consideration.
 
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