Boat Speed? Before and after remodeling?

[maxum247]

1989 maxum, 20ft. cuddy cabin with a 125 h.p. Force outboard, with power trim and tilt. As a cuddy my boat weighed around 2150 lbs. I beleive! I'm told that it ran 37 mph according to the speedohmeter when purchased new.

Just curious as to what the speed as a center console might be? The boat has lost a respectable amount of weight by removing the top deck, fold out seats, bulkhead, windsheild and carpet, and the hull height itself has been cut down about 8 in. I figure about 400 lbs. in weight has been removed. And probably about 150 lbs. or so will be added back by the time I'm done. There will be a 2 to 3 foot bowcap with bulkhead, and washboards, about 6 to 8 in. wide added and the center console made of 1/2 in. plywood with a built in seat, that's about it for weight that will go back into the boat.

Here are some before and after pictures, minus the bowcap and washboards. Pictures aren't so great, but maybe will help ! Thanks!

 

[MikDee]

Re: Boat Speed? Before and after remodeling?

Depending on how healthy that 125hp force is, I'd guess 40-45mph, the reason being my 19' Bayliner bowrider Ski boat (similar to a Bayliner Cobra) the hull weighing about 1500lbs, about what yours does, and just makes 40mph with my worn 125hp Force (115lbs compression overall).

 

[Chris1956]

Re: Boat Speed? Before and after remodeling?

Maxum, I do not think you will see any more than a small increase in speed maybe 1-2 MPH. This change is also within your speedo's error, so it is likely you will not really be able to tell and difference reliabally.

As a test, how much speed would you gain it you ran full speed with three in the boat, and then with one in the boat? That represents your 300# weight change.

 

[tashasdaddy]

Re: Boat Speed? Before and after remodeling?

you are going to have to do some experimenting to get the motor set up properly, you have drastically changed the center of gravity of the hull. getting the height and trim correct are going to do a lot for the performance.

 

[Texasmark]

Re: Boat Speed? Before and after remodeling?

10-4 on what tas said. I can trim my nose (bow) into the water and easily knock 10 mph off my speed. So you essentially pulled your nose out of the water and should expect more speed. You'll just have to find the sweet spot to get it all.....for the current load you're carrying at the time....as stated.

Mark