First, I realize I've been crying wolf on this rebuild deal for quite some time now, but I simply have to do something with my 58. I still don't know exactly what it's going to take to rebuild the starboard that has a burned piston, but given today's climate, I'm thinking of other options including a repower with smaller engines. Truth is, I really love this boat, and I'm not going to just give it away.

Hull speed for my boat is approximately 10 knots, and now that it's destined to become a river cruiser, that's really all the speed that's practical not to mention economical. Having run this thing over 1,000 miles on one engine has let me realize that making 10 knots is not that bad. I'm also considering the possibility of putting the boat into a river charter as a bed and breakfast type operation as it's located in a prime area for such a thing.

I'll try not to ramble too much on this one, but I'm looking for ideas as to how 671N's, for example, may work on this boat. I realize there are more efficient engines to be had other than the 671's, but I doubt the difference in cost would justify them. No doubt there would be a huge weight savings which would further enhance fuel economy. I'm assuming I could sell my 12V71N's for enough (or close to it) to come up with a pair that have been rebuilt. The port engine runs like a top and has less than 1,000 hours on it.

My questions are as follows:

Will 671N's be sufficient to provide hull speed without overworking them?

Can I change gear ratios in the transmissions to allow using my current props and shafts or am I looking at replacing those as well?

Last but not least, has anybody heard of anyone doing such a swap in this model?