18' Foot Gentry

I am in the planing stages of my first wooden boat build and like anything else I touch there will be changes. Before I get started I was wondering if a transom around 5 to 5 1/2 foot wide would float a small block 5.7. The plans have the engine just forward of mid and the cockpit aft in which I still may have to build it this way. Would like to stretch it to 21', this boat at the widest has a beam of 7'. Any ideas on this build?

Thanks
elwood

 

Why would you want to stretch a 18 foot boat to 21 feet Its likey to go out of proportion and if the boat has any inherant problems then it could make them worse !! . The Glen L Gentry says it will take a 5.8 anyway !!:?:

 

The reason I want to extend it to 21' was to enlarge the cockpit, kinda like the 22' Zimmer Palm Beach Runabout. Both of these boats have the engine forward of the cockpit . What I didn't like about the Zimmer was the 5'6" beam where as the Gentry has a 7' beam. My plan was to start at the widest rib and move the transom aft 36" which would give me a bigger cockpit. I know I would have to float test this with the proper weight arrangement before actually finishing the deck and floor.
My other option would be to change the transom to a stern drive and increase the dead rise.

Thanks

 

This is actually something similar I have thought about. But I had an idea to use a 20' Riviera hull, and build the deck layout as a rear cockpit.

My 2 cents.

L

 

I have thought about something like that but was thinking that since the Gentry already had the engine forward and a wider beam it might be a little more forgiving. It doesn't really make since to me how the Gentry even performs the way it is set up, I would think adding the length to the transom it would improve it.

Elwood