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Thread: 130hp two-stroke swap to 90hp four-stroke

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    Default 130hp two-stroke swap to 90hp four-stroke

    I have an older 19' Almar (aluminum) boat with a custom hard top. It has a 130 hp Yamaha Saltwater Series 2-stroke prop on it and was wondering if a 90hp fourstroke prop would be enough to get it on step with a few guys and possible moose on it? I mostly use it on the saltwater but plan on hunting the Yukon one of these years. At this time, I don't plan on running a jet on it but I guess you never know... The 130 Yamaha will push it over 40 mph, presently I cruise at 3700 rpm, around 27 mph. Thanks for any input or experience anybody may have in swapping outboards. Also, does anybody know what kind of value a 1996 130 yamaha s.s. has? Thanks.

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    Member pacific23's Avatar
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    I would go with a 140 to 175 4stk OB , the 2 smoke has double the torque as the same HP 4stk so if you want the same performance has your old 2 banger you will have to go as big or bigger 4 banger

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    It'll probably get up on step, with the right prop and with the weight distributed correctly throughout the boat. When I first bought my 19' Pacific skiff, it had a 90hp Honda on it. The 90 doesn't run very strong, IMO. I did haul some pretty good loads with it though. I recall 4500 Rpms at 22mph. Left me wanting more! I went from the 90 to a 130 Honda. Big step up. Then went from the 130 to a 150 Yamaha 4 Stroke. Another big step up. Fuel economy is very good too, as I can stay at the 4k RPM that gives you the best fuel economy.

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    Member Akgramps's Avatar
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    If I recall the Almars are a good boat and fairly heavy, consider the Suzuki DF140, as light or lighter than most 115's and they are economical to run. I run one on a 19 foot boat and the 140 is plenty with the prop and just enough with the jet.
    “Nothing worth doing is easy”
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    Thanks for all the replies. I was thinking a 115 might be the choice, but as akgramps points out, the Suzuki 140 is around the same weight, plus it keeps me open to the jet option. This might be like opening a can of worms, but are most newer outboards around the same quality? Also, would a direct injection 2-stroke be a good option? Most people are always talking about four-strokes but them fancy new 2-strokes might be close competition. Thanks again.

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    Member Akgramps's Avatar
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    Quote Originally Posted by roybekks View Post
    Thanks for all the replies. I was thinking a 115 might be the choice, but as akgramps points out, the Suzuki 140 is around the same weight, plus it keeps me open to the jet option. This might be like opening a can of worms, but are most newer outboards around the same quality? Also, would a direct injection 2-stroke be a good option? Most people are always talking about four-strokes but them fancy new 2-strokes might be close competition. Thanks again.
    Hard for me to be objective here as I have not owned a new 2 stroke and really like the modern 4 strokes, I like the way the motor sounds whichI know is kinda corny...........but on long trips noise its a big deal (to me anyway), and the Suzuki is really quiet. At most throttle settings except for WOT you can carry on a conversation in normal tones. Noise can get annoying and add to fatigue, you just get tired of it, of course there are earplugs and headsets as a option.

    Interestingly enough the DF140 is lighter than Suzuki's own 115 and Yamahas 115 as well. I think its really comparable in weight to the 2 strokes.
    “Nothing worth doing is easy”
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    I would not cut horsepower when going from a 2-stroke to a 4-stroke. A friend of mine went from running a 140 hp 2-stroke suziki to a 115 4-stroke suzuki on a 20 alumaweld skiff and had nothing but problems (load capacity, rough water power, additional weight from the motor, and the way the boat acted overall). If anything, when switching strokes, look for an increase in horsepower. Gas consumption will still decrease, you'll have power when you need it, and you won't be scared to pack a load. Just my .02.

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