Comparing thrust 2.5hp VS trolling motor

[Moody Blue]

Tossing around the idea of adding a trolling motor to my boat, a 15ft deep V fiberglass hull. Main motor is an 80hp. Would be used for occasional fishing and as an emergency backup. Not alot of extra room to add more batteries for a trolling motor so was looking at a small gas motor. Don't want alot of extra weight hanging off the back of the boat all the time so want to keep it as small as practical.

Does anyone know the comparative thrusts between say a 2.5hp 2 cycle vs a 55Ib thrust electric trolling motor as an example?

 

[Moody Blue]

Re: Comparing thrust 2.5hp VS trolling motor

I found this article http://ezinearticles.com/?Choosing-an-Outboard-Motor-For-Your-Dinghy&id=2008077 that suggests a 3.5hp equated to between 66 and 90 Ib of thrust. Can anyone offer any other input?