How many Horse Power do you have?

[JohnnyRudeClassics]

My 1963 Evinrude Fastwin 18 HP makes 19 or 20 mph ( by GPS ) on my 365 class SIB.
Unfortunately it seems she likes drink about 3.5 or 4 gallons per hour at WOT.

Last weekend, I finally found me one of the old 10 HP Evinrude's with the George Jetson styling.
... ( like the '63 18 HP Evinrude has )
I am very anticipated to see if I will be satisfied with that engine on the back of my SIB.
Hoping for 15 MPH and 2/3rds the fuel burn rate.

 

[jrs_diesel]

9.9 Johnson 2 stroke. I am rebuilding a 6 HP johnson, also a 2 stroke that will see service on my SIB. I am partial to the two strokes due to the power delivery, simplicity, and usually somewhat lighter weight (9.9 is 72 lbs, and the 6 is 56 lbs). I did have my Mercury (Tohatsu) 6 HP 4 stroke on my SIB and was not impressed. Felt kinda gutless and had a harder time getting on plane (with just me on it).

 

[ronaldj]

There is no question that the 4 stroke motors have a weight penalty that all but erases any performance gains you were hoping to see. Also the 4 stroke engines are breaking transoms. I have seen 2 boats in successive weeks have a transom failure due to the weight difference between the 2 stroke they were using and a 4 stroke of the same horse power but a much higher weight. When replacing a 2 stroke motor you have to buy the highest rated horse power that weighs the same as your 2 stroke motor. In almost every case it will mean down sizing your motor. It is unfortunate, but it is reality until the 4 stroke motors come down in weight

 

[ggirf14]

I have a 50 hp Merc. 2 stroke that I should try for the first time in a week from now.

 

[Sea Rider]

I'm hoping this 2003 2 stroke 8hp merc is enough to get me around on my new Saturn SD470. I did the weight calculation thing and said I should be able to hit 20mph

One must never lose enthusiasm, but no way doing 20 MPH with a 8 HP Mounted on a huge and heavy 470, too much hull drag to overcome. Will need min a 20 HP for that to happen. Has that combo already had ts maiden voyage ? Did it plane out easily or with difficulty ?

Happy Boating

 

[Peter_C]

Hey Peter, what kind of speed do you get at wot on that zodiac?

25mph on flat water, and around 28 as the water gets rougher, as in bouncing off the water. It will easily plane with 4 scuba divers, and all of our tanks, plus gear (We are cold water divers). I can run about 20 mph loaded as such, but rarely get a chance in the ocean. It is within the max RPM range though, so the prop should be about right. The motor has a Stingray wing on it, so it looses a little top end, but makes up for it by planning at far slower speeds, which is more important to me.

 

[alanfox55]

No Title

I have a 30hp Mercury on my 14ft Sea Eagle.

 

[fbpooler]

Went from a 25 HP two stroke to a 30 HP four stroke on our hard hull boat. When you open the throttle, you see a great difference. The 30 gets much better gas mileage and idles like a dream, but it just does not have the initial power or top end of a two stroke. We miss the two strokes but have small two strokes for portable use thankfully.

We went from a 14 ft boat to a 17 ft boat, as the 14 footer struggled with the weight of the 25. The 30 would have sunk it. You could manhandle the 25, but anyone who could manhandle the 30 would scare me

We sold two two strokes in the last year or so, and there is an active market for them. When we advertised the two strokes, people came out of the woodwork to buy them.

Comparing how much horsepower someone is using with the variable being the size of the boats is a waste of time. That is apples to oranges and has no meaning.

The thinking behind the move to four strokes must come from the same people who gave us gasohol

 

[alanfox55]

No Title

You can still get a new Evinrude 2 stroke but they are heavier than the older motors. The older the motor the lighter the weight...usually. By the way you can find lots of older two strokes that run great. I just sold a 1972 Johnson 6hp and that motor would start first time every time and run great all day. My Mercury 30hp is a 1997 that looks and runs like new.

 

[ronaldj]

Where in North America can you still get a Portable 2 Stroke motor

 

[Chopperbill]

Take off one 9.8 and make a poll for one 20 hp

 

[mrdrh99]

Nice.... Do you keep your motor on transom while towing?

 

[Chopperbill]

Nice.... Do you keep your motor on transom while towing?

Yes, on my aluminum flat bed ATV trailer with the launching wheels attached. Motor weighs in at 97# only 16# more than the Tohatsu 9.8. Both are rated lightest in there class.

 

[JohnnyRudeClassics]

Finally got out last weekend on my 365 class china sib
with that 1963 Evinrude Sportwin 10 HP I bought back in June
so I guess it is close enough for +1 to the 9.9 columns

Would still like to see a tally for 18 HP, there are at least 2 of us here between Sea Rider and myself