In practical terms, a large single propeller is more efficient at
providing thrust than 2 smaller ones, given the same amount of HP.

In terms of thrust, no there is no difference.

Evan Gatehouse

Matt Colie wrote:
Bob,

The answer is - Yes - to both

Somehow I am certain that you didn't ask the entire question, but I can
only guess.

If you are asking will the boat go twice as fast - No - again to both

This then comes into hull dynamics that will take much more information
effectively answer.

Matt Colie



Robert or Karen Swarts wrote:

If I use two 30 lb thrust motors, is that equivalent to one 60 lb
thrust motor?

Do two 9 hp motors equal one 18 hp motor?

In terms of boat performance, not necessarily theoretically.

Thanks,
Bob Swarts