3.7L Mercruiser Engine?

Without changing the gear ratio in your outdrive, a carb model 4.3L V6 . This is providing that your engine bay has the room to accommodate a V motor ( the 4.3 is about the same length as the 3.7, but 1 1/2 times as wide). You may have to "detune" the 4.3 - as simple as dropping the WOT rpms 400-500 rpm. You will also have to re-prop the outdrive - the 4.3 has a significantly different torque curve than the 3.7.

There are lots of remanufactured 4.3 crate motors available- just google mercruiser crate motors.

This is a world wide web site, and you haven’t told us where you live on this planet of over 200 countries. In short, you know what “local” means to you and we don’t.

I’ve also got friends in Australia who regard the guy living 70 miles along the road as being local to them. They wouldn’t understand my cousin in London who only regards “local” as being anywhere within a maximum of just 10 minutes walk from his front door.

So there’s no point me recommending you a workshop I know in Singapore and another really excellent one in Bangladesh which would happily rebuild your Mercruiser to a high standard if you live in Brazil or perhaps somewhere in the USA.

Direct your question to the manufacturer of the outdrive.