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Old 06 February 2018, 13:41   #1
zip
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Which is faster?

A boat with a single 4 stroke 300HP or with twin 150HP 4 stroke?
Iím thinking with a single engine you probably drop some weight, so is it faster?
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Old 06 February 2018, 13:51   #2
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This isn't close.....single will be faster if it will get boat on plane.

Nothing to do with weight really but it helps, only 1 gearbox to push and more hp do with it, a much bigger prop turning at higher rpm.

Twins of 150hp is about a 200-225hp ish single performance wise.
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Old 06 February 2018, 15:13   #3
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Quote:
Originally Posted by dubrus View Post
This isn't close.....single will be faster if it will get boat on plane.

Nothing to do with weight really but it helps, only 1 gearbox to push and more hp do with it, a much bigger prop turning at higher rpm.

Twins of 150hp is about a 200-225hp ish single performance wise.
As above!

A 2nd like for like lump gives you about 30% higher speed, I heard once a third engine gives you just another 2% top end!!

Itís all about drag

However once youíve had twins itís hard to go back to a single, very versatile for many reasons
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Old 07 February 2018, 04:18   #4
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However once youíve had twins itís hard to go back to a single, very versatile for many reasons


Very true I miss mine
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Old 07 February 2018, 15:09   #5
zip
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Thanks for your input gentlemen.
I’m researching my next sea going rib, and I think I’m going to go with a big monster outboard.
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Old 08 February 2018, 07:56   #6
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Put a 400R on it.

Single engine = less drag, less maintenance.

Twins is not really a requirement in the United States, due to our wonderful Towboat / Seatow coverage.
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Old 08 February 2018, 08:36   #7
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Yep, that is quite the monster motor.
If I go with another 730 or 733, I will probably stick with max rating of 300 HP.
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Old 08 February 2018, 16:31   #8
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Single all the way. I drive a boat with a single 300 Suzuki and handling and performance are so much better than twins.

I drive an abalone commercial boat with twin suzukis where I'm constantly working trim and trying to keep rpm equal. I also drive a gemini commercial dive rib for a friend from time to time with twin Yamahas which is also a pain compared to single. The extra weight on the back of the big gemini with divers onboard often means the back of the boat is constantly filling in a following sea at anchor.

Double the weight.
Double servicing costs.
Double the drag.
Etc etc etc.

All the boats I've been on with twins struggle to perform on just one engine, the offset mounting makes Them hard to get up on the plain. My mate recently did a gearbox on one of his twin 250 suzukis and had to limp home on one engine as the boat wouldn't plain on a single.
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Old 09 February 2018, 04:50   #9
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Single all the way. I drive a boat with a single 300 Suzuki and handling and performance are so much better than twins.

I drive an abalone commercial boat with twin suzukis where I'm constantly working trim and trying to keep rpm equal. I also drive a gemini commercial dive rib for a friend from time to time with twin Yamahas which is also a pain compared to single. The extra weight on the back of the big gemini with divers onboard often means the back of the boat is constantly filling in a following sea at anchor.

Double the weight.
Double servicing costs.
Double the drag.
Etc etc etc.

All the boats I've been on with twins struggle to perform on just one engine, the offset mounting makes Them hard to get up on the plain. My mate recently did a gearbox on one of his twin 250 suzukis and had to limp home on one engine as the boat wouldn't plain on a single.
Your mate wouldn't have got home at all with a single!! Lucky he had the redundancy of a second engine...........
I've run both singles and twins and would always choose twins over a single lump

Double the fun
Double the fun
Double the fun
Etc etc etc
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Old 09 February 2018, 09:15   #10
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I think for my application a big single is the best option.
Looks like Yamaha, Suzuki, Mercury, and Honda are my premier choices.
Not sure why Yamaha is so much higher in price though.
Suzuki is what I am leaning towards.
What you got?
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