26 Crestliner Rampage twin engine 350 ,260 hp.
I am plannig tgo rebuild to singel bigblock around 450 hp.

What will be the result??

Good or bad idea??

The result, a lot of work. thats a big boat for a single. You may upset the balance and make it bow heavy. What drive are you planning on using? What is wrong that has you concedering the the rerig? My first thought is it's not a good idea.
Jim

So you are going change the stringers and reglass the transom?????? sounds like a lotta work for nuttin. Small blocks are cheap and you could just add some HP to them for less money and a lot less work.

Hi again

I live in Europe everything is expencive.

1litre gasoline 2,22 usd (1 gallon 9 usd)
The service cost 3 times US prices

Fountain 27 Fever most of the boats are with singel engine
Same with Formula 27 Fastech

Even though the hull on the Crestliner are older it is only 26 feet and weight without engines are 4000 pounds

And the favt that I am buying the boat without engines and drives are also the reason that i consider a singel engine.

IMHO, it's a project you'll never finish once you see how much work is involved.

I have a local boatbuilder who rebuild the transom for a reasonable price.

From the test in Powerboat Mag the boat did 60 mph
with the twin smallblock 260 hp installation.

Well anyway, if I keep the boat as is I need to install 2 engines
and 2 drives.

DO anyone have any expirience with kind of the same experiment?? twin to singel??

I understand your concern of equipment, fuel, nd maintenance cost but I think the overall project does not make sense regarding the refurb cost and performance changes being considered. I'm not an engineer but my $.02

If it was me I'd be looking for a pair of nice, fuel sipping diesels in the 250 to 300 HP range. If you plan on keeping the boat for a long time the increased efficiency and reliability will pretty much pay for them. Just my $.02 worth........

Monoco20, given the situation it may not be such a bad idea. I would expect a little loss in performance. You may also need to change stringer configuration. Good luck.
Jim