20HP vs 9.9HP on a 228?

luckydude

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I'm curious if anyone put a 9.9HP Suzuki on a 228 and then did the conversion to get 20HP out of it (well documented on the hull the truth).
I'm wondering would 20 hp move my 228 faster, and if so, how much?
 
20 hp will not plane your boat. So you are limited by hull speed, which is about 7 mph. The difference in performance would be negligible.
 
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I have done the 9.9 to 20 hp suzuki change. It was a 16ft aluminum setup like a bass boat. Remote steering and throttle.
In NJ, almost all lakes are limited to 9.9HP if they allow gas at all. So buying a 20hp was not an option.

The change required an ECM, a throttle plate and a new prop.

Worked GREAT!

You will double the HP. You will need a new prop. You should prop to gain "power".
You will gain power to start and stop and run at lower throttle.
You are using for trolling so speed is not the goal for you.
You will not get anywhere near planing. If you want to troll faster than 4mph , use your main motor.

Boats.net
Screenshot 2024-11-22 at 8.33.42 PM.pngScreenshot 2024-11-22 at 8.34.16 PM.pngScreenshot 2024-11-22 at 8.35.02 PM.png

props are about $60. You would want one designed for use as a trolling kicker on a large boat.
 
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I'm wondering would 20 hp move my 228 faster, and if so, how much?
It depend for what you wan't to use the 9.9HP.
Here we use them exclusively as trolling motors for slow speed trolling below 1 knot.
If you raise your HP then you may become too fast, if slow speed trolling is the reason for the 9.9.
Chris
 
It depend for what you wan't to use the 9.9HP.
Here we use them exclusively as trolling motors for slow speed trolling below 1 knot.
If you raise your HP then you may become too fast, if slow speed trolling is the reason for the 9.9.
Chris
I don't troll slower than about 2.5mph so I think that part would be fine. The reason I'm considering it is I have a single main engine and can't get more than about 5mph with the kicker as it is. If my main became disabled, I'd like as much speed as possible out of the kicker to get home. If I could get to 7mph that would be an improvement.
 
Ok, then i would guess that the upgrade to 25 HP will make the boat a bit faster but not sure if 2 knots.
I know that the here very popular upgrade pulling the air restrictor disk but no ECU swap from 40HP to 60HP change makes a noticeable difference.
If you are willing to pay for the necessary parts then do it, but consider the added expenses for a new prop, and probably for several new props to find the best one to reach your goal.
Chris