Engine feeling 286

I have a feeling 286 with Yanmar 1GM 10 9hp with a three-blade propeller. When is the weather is calm my speed is 4.5knts. When the sea is rough with wind from the bow my speed drop to 2knts. I want a new engine for safety reasons. The space for the engine i think is to small. What is the best engine like 16hp + nani, volvo penta, scam or 2gm yanmar. Thank s for the help

Here is a first answer from Xavier who has a 286SP in Cambril - España , thank you Xavier :
Hello
I ve a Yanmar 2GM20 with a d-360 p-220 fixed propeller

Thank you for the help. I found an Yanmar 2GM20F anf if is ok i take it.