2 engines vs 1

Not really sure which part of the forums to put this in but here goes. I am looking to purchase another boat in the 27-30 ft range. I am finding lots of choices but don't have enough experience as to which would be better.

I will be operating the boat in freshwater only, weekends on lake etc. I want a relatively fast boat.....

I would like to here the pros and cons of two engines versus one. Most of the choices I see are a single 454 or dual 350's......

which package would yield more speed on the same boat.

Re: 2 engines vs 1

The duals will be faster and burn more fuel.
You will have a second engine to get in on should one fail.
Maintenance costs will be double and may be harder to service since do not have as much room on the sides.

Re: 2 engines vs 1

2 x 350s is gonna be faster than a single 454 . . . Sorta. A 385 hp MPI 454, is gonna be pretty close to two carbed 230 bhp 5.7s . . . 2 x 300 hp 350 mags will blow that single 385 away. A single screw is considerably faster than twins of the same combined power. Twins are less efficient cause they got mo stuff in da wawa. They be mo fun tho too. Mo fuel, but mo fun.

Define "relatively fast".

Edit: Sorry Boatist, simultaneous post.

Re: 2 engines vs 1

You didn't say what kind of boat you are thinking about and that makes a huge difference in what you choose.
My expenience is with cruisers so that is what I am talking about here.
27 feet is about max for a single engine if you want good performance.
It won't be fast but that is relative. A deep V 27 will give you about 32 miles per gal. A flatter bottom maybe 40.
I have a 2850 Bayliner with twin 305's. It does not count the swim platform in length and is 10 feet wide. It is a heavy boat, perhaps 11,000 pounds. Maybe a little more.
It is a 40 mph boat.
Doug

Re: 2 engines vs 1

dmcb said:

You didn't say what kind of boat you are thinking about and that makes a huge difference in what you choose.
My expenience is with cruisers so that is what I am talking about here.
27 feet is about max for a single engine if you want good performance.
It won't be fast but that is relative. A deep V 27 will give you about 32 miles per gal. A flatter bottom maybe 40.
I have a 2850 Bayliner with twin 305's. It does not count the swim platform in length and is 10 feet wide. It is a heavy boat, perhaps 11,000 pounds. Maybe a little more.
It is a 40 mph boat.
Doug

Click to expand...

I think we missed a decimal place or 2 here. If you get 32 miles to the gallon you must be getting towed !!!

Re: 2 engines vs 1

i think he meant 32 and 40 miles per HOUR?

Re: 2 engines vs 1

Well I am looking for a 27 foot SeaRay Sundancer and have seen several motor combinations, single vs twin.

Relatively fast.....hmmmm.... would like to see a cruise in mid 30's if possible....

also on the twin/single idea I want a generator and have seen some installed on both types, but I cannot figure out where they are putting it on the twins.

Thanks for all of your input guys......

Re: 2 engines vs 1

That is about the breakeven size boat for single versus twin engines. My grandfather has a 28 ft Sea Ray Sun Sport with twin 350 MAGS, top speed is around 55 with Bravo 1's turning Mercury Revolution propellers and the exhaust on the thru-hull setting. The engine compartment is very tight with the twin engines, servicing anything on the side or rear of the engine is a major chore. Sundancers are heavy cruisers, they are really not designed for top speed. If I were you I would go for the twin engines, I think that is just too much boat for a single 7.4. If you want to stay with a single engine and you find one with a 8.1 there is a company called Raylar that sells kits to hop up the engine.

Re: 2 engines vs 1

Twins give you a level of control at low speed that you will never achieve with a single.Essentially with a single you need the inertia of the boat to dock.With twins that is not nessesary.You can crawl into the marina with twins ....and do a 360 degree turn while in a stationary position.
You can handle larger boats much easier with twins.

There is also the added safety of having two.However as has been pointed out twice the maintenance,twice the cost,twice the gas....two times nearly everything
Likely the twins are a bit faster on the same hulled boat but not by as much as you might think.

Re: 2 engines vs 1

I am a fan of twin engines--I have a 1988 Regal 280--twin merc 260's---my thought are I'm not worried about top speed---how often do you go WOT for very long???---I want to cruise at a good speed without pounding the motors---my boat is 28' long and in the 10000 lb range--I can run 46-49 mph at WOT---but I can cruise very nice at 3200 rpm at 34 mph---thats what I look for---also 2200 hours--twins engines--towed many boats in---NEVER had a tow line on the front of my boat---if you boat in a rural area--twin engines are much safer--good luck---Steve----PS I forgot to talk about resale??????

Re: 2 engines vs 1

I was always told to get twins, always. All my other boats were single screw up to a 25 foot with a beam under 9 foot. I felt more than comfortable docking in all types of weather and currents - I had no worries. I wanted a wider beam and more room so I ended up with a 10 foot beam and twin 350s in a 28 Larson. I was a bit skeptical at first but all my friends were right - there is no better way to fly. Safety - always have a way home. Speed helps - running in the 50's is always fun once in a while. The thing that made me grin was docking. It is a whole lot easier manuvering with twins.

Safety is worth a couple more bucks in gas and maintenance to me...

Re: 2 engines vs 1

Ya I meant 32 mph. Funny thing is I saw it and thought I corrected it. Must have hit post instead of save.
I had a 27' Bayliner with a 260hp 5.8 Ford/OMC.
That was the 32 mpH boat. When I loaded it for a month anchor out, it was a 29 mph boat.
Weight is the enemy here. Add a genny, and, and, and, well you see where this is going.
The type of bottom is important here also. A deep V will give a good ride but will be slower. A flat bottom will pound but go faster.
You might think about a Honda for your genny. Portable and light.
I kept my EU2000 securely fastened to the front deck. Open the hatch and start. Worked well for us. Puts weight where you want it also.
The best thing is to sea trial what you are thinking about.
Remember this however. A boat for sale usually has all the gear removed. The fuel usually isn't full. May be no water, food, and so on aboard.
Carefully consider this as it won't perform nearly as well when all this is added.
A few extra people might level the playing field a little.
Water is 8#/gal. Gas 7#/gal just for starters.
If you want to cruise in the mid 30's, I think you will have to go with twins.
Doug

Re: 2 engines vs 1

We were out with a friend today in Biscayne Bay in his 42' SeaRay with twin diesels. When we got back to his slip I watched him back it in moderate wind using just the transmissions and a slight kiss of one throttle or the other from time to time. It was like watching an artist - no wasted motion - no worries about hitting the dock or the boats on either side - a greaser as a pilot would say after a smooth landing - something I sure would like to learn how to do.

That wouldn't have happened with a single,

Re: 2 engines vs 1

Guys thanks tremendously for all the input, after reading what all of you have described above I am able to make a choice. I will opt for twins since as mentioned above I would like to cruise in the 30's, I do most all of my maintenance so that could help defray some of the cost.

Now to continue on, I have seen some twins with V-6's, I have always been a V-8 man myself so I guess I am answering my own questions in that respect.

Thank you....

Re: 2 engines vs 1

My opinion is to allways buy a little more power than you think you will need--remember loaded with people-gas -beer-water--all the junk that you will have on the boat--you can allways pull the throttle back---resale-resale -resale----buy the V8's--good luck--Steve

Re: 2 engines vs 1

Geez DMCB that 2850 must have sucked up about two tons of water. The 2850 Bayliner with twin 305's was rated at 5770 lbs. dry.