Single engine for liberator 261?

[ChrisO86]

Hi guys and girls!

I?m new here on the forum. me and my friend isthinking of buying a four winns liberator 261 (we live in sweden). and none of us are not a big fan actually of twin engines. but we are in love with the 261.if we ditch the engines and put in a big block engine instead, would that work? or is the boat to heavy? IF it?s correct info i have, it would weigh around 3000 kg with twin and around 2500 with one engine? calculated with a 502 mag and bravo 3 drive. what would you recommend for this boat if so? 7.4 330 hk carb, 7.4 mpi, 502 mag efi, or maybe a 496 mag/ho. . we do not need a very high top speed. just want a good crusing speed instead with a descent fuel consumption.

 

[alldodge]

Howdy

I would stick with twin small blocks. You can reduce some weight going to a single but if you stay out of the throttle, the twins will do just as good on fuel. Being able to get home if one engine quits is also a nice feature.

If you really just want to do it you will have to redo the stringers and the big block will need to sit lower then the twins. I would recommend the 502 MAG or MPI, but a 496 next, then a 7.4 MPI (a 7.4 with 502 heads and EFI). Match that with a bravo 3 drive in a 2.0 ratio

 

[Scott Danforth]

A pair of 6.2 liter stroked small blocks would be my choice

 

[ChrisO86]

Howdy

I would stick with twin small blocks. You can reduce some weight going to a single but if you stay out of the throttle, the twins will do just as good on fuel. Being able to get home if one engine quits is also a nice feature.

If you really just want to do it you will have to redo the stringers and the big block will need to sit lower then the twins. I would recommend the 502 MAG or MPI, but a 496 next, then a 7.4 MPI (a 7.4 with 502 heads and EFI). Match that with a bravo 3 drive in a 2.0 ratio

i have to think about twins. but it is over all more costs and repairs with twinsbut i am also aware that it isn?t cheap to own a boat for that matter.. if i put in a 502 mag / mpi, what du you think i can get in speed? crusing and top. is their anybody here that KNOWS what a 261 liberator weighs with twin smallblocks? on the internet i found a weight from 5500 punds upp to 6500 punds (twin 460s). but i don?t know how trust worthy those sites are:

http://boatspecs.iboats.com/Four_Win...89/bp/66b34142

http://www.boatshop24.com/en/-26-fou...wrFMoUmebFR.97

 

[alldodge]

i have to think about twins. but it is over all more costs and repairs with twinsbut i am also aware that it isn?t cheap to own a boat for that matter.. if i put in a 502 mag / mpi, what du you think i can get in speed? crusing and top. is their anybody here that KNOWS what a 261 liberator weighs with twin smallblocks? on the internet i found a weight from 5500 punds upp to 6500 punds (twin 460s). but i don?t know how trust worthy those sites are:

http://boatspecs.iboats.com/Four_Win...89/bp/66b34142

http://www.boatshop24.com/en/-26-fou...wrFMoUmebFR.97

5500 to 6500 pounds sounds about right between small block and big block V8's.

I would guess 415HP 502MPI would get you to 60MPH, maybe a tad more. Should cruise in the 30 to 35 range

 

[ChrisO86]

5500 to 6500 pounds sounds about right between small block and big block V8's.

I would guess 415HP 502MPI would get you to 60MPH, maybe a tad more. Should cruise in the 30 to 35 range

if that?s correct that you say. that sounds to be very good numbers for me. when i don?t chase high top / crusing speed. do you think that the boat would go up to plane in a descent time with a 502 mag? i am also registered on offshoreonly forum. but there is another guy who says that his libby 261 weighs 8500 pounds with trailer? i am very confused actually. is a BIG difference between 5500 and up to 8500 pounds. i can take if the boat lands on 6500-7000 pounds with twins. and if i calculated it right. the weight would drop with 400-450 kg if i convert from twin 5.7 / alpa to 502 mag/mpi with bravo 3. then the totall would be around 2500 kg for the boat with a single engine?

 

[alldodge]

I to am a member of OSO, and the guy (Mild Thunder) said he had a 241 (not 261) and the boat had a single 540 (not standard Merc motor) weighted in at 8500 pounds including trailer. The trailer will weight 1000 to 1300 pounds. The weight figures your looking at on the web is dry weight. Dry weight means no fuel, water, life jackets, anchor, all kinds of gear.

You started this thread and the one on OSO with the idea of going from twins to single because saving maintenance and less weight. You don't care about top speed but you keep coming back to it.

Example: my 27PC dry weight states 9500 pounds, it now weight closer to 11000 because of fuel, water, generator etc. My 27 tops out at 47 MPH with a single 502 MPI with Bravo 3. So your going to be a foot longer and a few thousand pound lighter. So if your at even if your at 4000 Kg you should be able to be fine.

As before, changing from twins to single I don't think is a good move. Your boat your money and this is just my WAG at your questions

 

[funk6294]

Here is a link to Four Winns catalog. Scroll down to page 85 for the 261 liberator.

Edit: my link may not work right. You may have to click on the customer service link at the top of the page and the look for the link that says catalogs on the right and then look for your model year. I linked to the 1990 fast facts page and it had all power options, weight and performance data available. Btw there no single engine options available.

 

[ChrisO86]

Here is a link to Four Winns catalog. Scroll down to page 85 for the 261 liberator.

Edit: my link may not work right. You may have to click on the customer service link at the top of the page and the look for the link that says catalogs on the right and then look for your model year. I linked to the 1990 fast facts page and it had all power options, weight and performance data available. Btw there no single engine options available.

Hi.

i?ve checked att owners manual but couldn?t find anything? i choose 1987-1994 sportboat. but their wasn?t any info about liberator 261 on page 85?

 

[alldodge]

With twin 350 weight is 6180
With twin 460 weight is 6800

100 gallons gas 6.15 = 615 lb
Battery 50 lb each
Max load gear and people 3640

http://www.fourwinns.com/upload/Documents/Catalogs/1990/Catalog.pdf

 

[ChrisO86]

With twin 350 weight is 6180
With twin 460 weight is 6800

100 gallons gas 6.15 = 615 lb
Battery 50 lb each
Max load gear and people 3640

http://www.fourwinns.com/upload/Documents/Catalogs/1990/Catalog.pdf

if those are correct numbers for twin engines, then would the weight be with a single 502 efi / bravo 3 be around 2400 kg dry weight. as i said, i?m not out after high top speed. IF there will be anyway maybe. it?s only a bonus. can i have a crusing speed around 30 knots. i?m good. but how fast it will plane is another thing also

 

[alldodge]

if those are correct numbers for twin engines, then would the weight be with a single 502 efi / bravo 3 be around 2400 kg dry weight. as i said, i?m not out after high top speed. IF there will be anyway maybe. it?s only a bonus. can i have a crusing speed around 30 knots. i?m good. but how fast it will plane is another thing also

As compared to original twin :noidea: