What speed to expect

[191 champ]

I have an 18' Grumman flat bottom that I put a front deck on. I'd guess the weight to be 200 lbs with trolling motor. I built the boat to fish Maryland electric only reservoirs but now I'm moving and may put an outboard on it. I ran it like it is with the deck installed, two group 31 batteries right behind the middle bench, three 31s in front of rear bench with my son and I (400 lbs) with a 9.9 hp motor one time and got about 9 mph out of it. I think the prop pitch was 9.25". The boat is rated for a 40 hp.

So what kind of speed might​ I get with a 20 hp, 30 hp, or 40 hp after I remove three of the batteries and by myself (200 lbs)?

Where I'm moving (Greensboro NC area) has several 800 to 3000 acre lakes that I could use this boat on. I'm​ not sure I could stand going 10-12 mph though which is what I would expect with my current 9.9. I have no experience with Jon boats to be able to even make a good guess.

[ncbass]

No idea....but welcome to NC!!

[Jwolff]

I have a 17' Lowe Roughneck that did 20mph with a 25hp Tohatsu 4 stroke with approx. 400lbs of dudes and a 12v trolling motor. Putting a 60/40 jet on it next week so we will see how that speed changes.

[n2ratfishin]

20-25 mph would be my WAG based on prior experiences.

[Bassbuster95]

my 1752 lowe with heavy aftermarket front deck, 24v troller, 2 group 31's, tackle and myself with a 40hp goes 32mph on a good day. add a person and deduct 3mph.

[191 champ]

Thanks, good input.

[King_Fish]

20-25 mph would be my WAG based on prior experiences.

X2.... go with as much HP as the budget will allow, unless there are limited HP lakes in NC.