I've recently built a 8' plywood dinghy that (in theory) seats 2 or 3 people at most, and l was hoping to put some type of engine on it, and since an outboard would be too heavy, l was thinking of putting an electric trolling motor onto it. l was wondering how much thrust l would need and which type would be the cheapest.

l would think 30 would be sufficient on an 8 foot boat..MinnKota is a good one, & can be bought at any Walmart. l have a 50 on my 18 foot boat, & it is almost too much, unless l run it on the lowest setting.. l had a small piroque at one time, & it had a 30. My bf cut the shaft, & mounted it on a swivel on the back, & ran cables from a ''Tee'' to foot pedals. He extended the wires where the on/off & speed controls were right beside the seat.The motor could kick up, if it hit something underwater, & it worked out very nice.( l am on his computer today, & l hope he does not find out)

On a boat that size , almost any small trolling motor will work on it- get the hand control- it will take less room to operate it in the small boat.Have fun!