Will a 15 hp be all that much better than my 9.9 hp?

I have a 14' Richline v hull that putts along at 12 mph with me and with 2 guys it will do 8 mph with a 9.9hp sea king. I am checking out a 15 hp evinrude for $400 I was thinking about upgrading. Is it going to make all that much difference with a 15 or do I need to go up to a 20-25hp to go faster and not sure if I really need a Bigger motor just thinking about it. What say you tinboats members. :roll:

I'd think you'd see a big difference with the 15 and and even bigger difference with the 20 . Not sure your boat is rated for a 25.

if im not mistaken 4 strokes have a little more power to them then 2's correct? if thats true then a 15 4 stroke would work probibly just as well as a 2 stroke 20.

Jay D said:

I have a 14' Richline v hull that putts along at 12 mph with me and with 2 guys it will do 8 mph with a 9.9hp sea king. I am checking out a 15 hp evinrude for $400 I was thinking about upgrading. Is it going to make all that much difference with a 15 or do I need to go up to a 20-25hp to go faster and not sure if I really need a Bigger motor just thinking about it. What say you tinboats members. :roll:

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Most 9.9's are really de-tuned 15hp. At those speeds, I'd say your boat wasn't planing yet. You need torque to plane, and there is not much diffrence in torque between 9.9 and 15hp of same displacement. If you have already tried a lower pitch prop, I'd waint and go for a 25, or whatever the cg max is.

With a 50% increase in horsepower over what you have now you should feel a substantial difference with a 15.

Jay D said:

I have a 14' Richline v hull that putts along at 12 mph with me and with 2 guys it will do 8 mph with a 9.9hp sea king. I am checking out a 15 hp evinrude for $400 I was thinking about upgrading. Is it going to make all that much difference with a 15 or do I need to go up to a 20-25hp to go faster and not sure if I really need a Bigger motor just thinking about it. What say you tinboats members. :roll:

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Can you provide info and/or pictures of your boat? Maybe your current motor is not up to snuff. Lots of variation in 14' v hulls. I have two 14'ers. One a 10hp will plane it and hit 15-16mph with 2 people. The other, it would take at least a 25hp.

MDFisherman57 said:

if im not mistaken 4 strokes have a little more power to them then 2's correct? if thats true then a 15 4 stroke would work probibly just as well as a 2 stroke 20.

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Mistaken...
15 horses is 15 horses...

He says the 15 dies when you try to shift into forward at idle, a buddy said it may be problems in the lower unit. I may wait a little while longer. I will try and post pictures of my boat.

I just replaced a 9.5 HP Evinrude with a 15 HP Chrysler on my 13 foot semi-V and my speed actually dropped slightly. The 15 has a whaletail that I plan to remove before I try again. I'm only getting 7.5 mph with 2 people on board with either motor. Both motors run great and have good compression, but I can't seem to get any speed out of either one.

I'm pretty sure my 1981 Johnson 15HP has the same powerhead as my dad's 1983 Johnson 9.9HP. The main difference being the carburetor size. As a matter of fact, I think there are a few threads on here where people just swapped carbs to upgrade from 9.9HP to 15HP.

As for the power difference, there's a noticeable feel of more power and better planing on my 15HP than my dad's 9.9HP. We both have riveted 14' jons, his 36" and mine a 42".