Mini V.or Something else?

Hello,and new to the site,Been into boats all my life ,Had many ,Getting in to hydro and v bottom,looking to build a Mini v ,but extend the length to 13 ft.what is the bigest engine i can install on it / with the proper mods,I know it's only realy rated for a 25-40 will the 40 be enougth,or should i buy something else,Really like the out champ boat look ,not sure what there called but some ran the 4-6 cylender in line motors,old school,looking to buy or trade for something in that rang ,i have a 4 wheeler posted on here has well .it's on boats and motors ,I thank you all that can help.People in the south see hydro 's,champs or any thing outher than a bass boat ,they think your crazy,i am ,i like having fun on the edge.I'm in Columbus .MS you can call me at 662-889-6677