speed difference in motor size

[TonyMe]

Hello everyone. Bought a second boat but a first with a outboard motor. The motor is a 9.9 johnson with the 15hp upgrades on it. The boat is a 14' deep V Grumman. The boat runs about 22mph. The max size motor that it can take is a 35hp. I was woundering about how much difference in speed there would be with a 35hp over my current motor. Most of the lakes I fish are trolling motor only but now with the gas motor have have some different options and wasn't sure if it is worth the extra wieght and the fuel usage to look for a 35hp.


Thanks, Tony

 

[Bondo]

Re: speed difference in motor size

Ayuh,.... Welcome Aboard, Tony,... I'd Guess ya might hit 30 mph... Maybe not...

 

[JB]

Re: speed difference in motor size

I think Bond-o is correct, maybe a little high if you carry all the additional fuel the 35 would need.

 

[cyclops2]

Re: speed difference in motor size

I have a 16' aluminum with 9.9 Evinrude or the 35 hp Evinrude. I had the 35 first. To slow as a bass boat. Too fast to troll. IMPOSSIBLE to start with a cord. EATS fuel. is loud on long trips.

9.9 with electric & recoil starter. PUUURRR fect !! If you want to catch fish.
I fish & move constantly. Everyday. 1/4 of a pull is a start every time. Or bump the starter key. No choking after first warm up.
Evinrude used a 15 hp engine for the 9.9 hp. in 1988.
I can almost run 7 days on 6 gallons.
Save the 35 hp money for someting else you would like. 2 people move along fine in wind & or current.

Foget the 35

 

[cyclops2]

Re: speed difference in motor size

A 14' & 35 CAN blow up & flip backwards in a decent wind. USE CAUTION.

 

[TonyMe]

Re: speed difference in motor size

Thanks for the fast replies. You guys have some of the same thoughts and concerns I was having on getting a bigger motor. I think I will just stay with what I have and be safe and save a lot of fuel.




Thanks again for the fast replies,
Tony

 

[pootnic]

Re: speed difference in motor size

Seems like your happy with your decision,must be good for your type of fishing/trolling.
I like the extra speed,even if only around 8mph more,that would bring me to a spot/home around 35% quicker(hope that about right).The newer motors and alot of older ones start just fine plus the newer motors(2 and 4)troll great and sip gas.My 30hp (87) takes 3 pulls cold,then a part pull after that.
Just don't get scared off the idea of a bigger motor because it would be un-safe.Your deep V is rated for a 35hp so for sure it will handle it....flip backwards??
Most people normally say,don't go less then 75% of the maximum hp rating for optimium boat performance.
Anyways,I think the 15hp is fine but if I could afford it,a brand new etec 25/30 hp.

 

[bonz_d]

Re: speed difference in motor size

A 14' & 35 CAN blow up & flip backwards in a decent wind. USE CAUTION.

Huh? My Lund S14 is rated for a 35hp which I have on it and it would have to be a very stiff wind to blow it up and over. If the wind is blowing that hard to blow it over you can be certain I wont be out in it in any boat!

Tony, I 1st had an 18hp on this boat and the top speed change between the 2 wasn't that great. What did change was the time it took to plane and the amount of weight I could load and still maintain speed. Remember for the most part RPM + weight + prop pitch will determine speed.

 

[metriccrescentwrench]

Re: speed difference in motor size

The boat runs about 22mph. The max size motor that it can take is a 35hp. I was woundering about how much difference in speed there would be with a 35hp over my current motor.

Going purely by the math and not taking into account extra drag caused by increased weight you'd be looking at around 33 mph. Realistically it'd probably be a bit less than that. As far as safety, I personally wouldn't be concerned using an engine that's within the rating of the hull. The extra fuel usage would be a factor, when I was a kid we had a small boat with a 7.5 outboard - it sure was nice to be able to go for what seemed like forever between trips to get fuel.

 

[TonyMe]

Re: speed difference in motor size

I still am looking to see if I can find something cheap. Biggest thing is I don't know how much I will get to use the gas motor and if I will get on any lakes big enough to need the extra speed. Most of the lakes around me are not real big with one being 20hp and under. We went on vacation last year on lake champlain in VT and there I could use it but don't know if we will get up there a lot or not. But up there I just need a bigger boat and motor.

Tony