Looking for some general info

[AstroTux]

Hi,

I'm presently designing my own 30ft Catamaran, and was wondering about how to go about determining the right sized engines for it?

I've no idea about final all-up weights yet for the boat, but I'd be looking at a couple of tons at least, I'm sure.

Any recommendations on manufacturer? I'd prefer economy vs. power, and want something very reliable. What sort of cost would I be looking at for new engines (I'd need two)?

Any recommendations on props?

Best regards,
Robin.

[gonzo]

If you follow standard design methods, you'll determine a displacement and speed target first. The HP of engines, props, transmission ratios etc. are calculated to attain those targets. You also have to take into consideration, hull fineness coeficient, dynamic lift, hydro and areodynamic drag, etc.