Reason for Max HP on a boat?

[dadgeff]

Sorry if this is a stupid question, my boat lists max HP at 70. Is this just because of weight or is there other reasons?

 

[Lowlysubaruguy]

Its purely inspirational. For those who decide there boat doesn’t get out of the hole fast enough or go fast enough they will buy a new boat. Its like the way they always seem to make new models that look cooler go faster. For the other 3% its so they dont kill themselves or others by cramming a 200 HP on that boat that can only safely handle a 70 HP

 

[GA_Boater]

Moved your thread to a better forum section.

Max horsepower is all about safety and is based on a US Coast Guard formula using the measurements of the boat. The weight of the motor does count into the max weight of the boat which includes the motor, gear and passengers.

 

[dingbat]

https://www.govinfo.gov/content/pkg/CFR-2002-title33-vol2/xml/CFR-2002-title33-vol2-sec183-53.xml

 

[Scott Danforth]

its based on the approximate forces trying to tear the motor from the transom. so a formula was created based on boat size which roughly corresponds

the load path on an outboard is a big lever arm clamped to the top of the transom trying to pry the transom loose from the boat.

 

[dadgeff]

Thank y'all. It was just something i was wondering about because I didn't want to pop wheelies LOL, but just to get to the fishing hole a little faster.

 

[Texasmark]

its based on the approximate forces trying to tear the motor from the transom. so a formula was created based on boat size which roughly corresponds

the load path on an outboard is a big lever arm clamped to the top of the transom trying to pry the transom loose from the boat.

Don't laugh. Back in the '65-68 timeline, I had a very casual-distant acquaintance that built his own wooden boat. Powered it with a "Fat 60". First time out, he idled out of the boat basin and hammered down on the throttle.......results: The only thing holding the engine (and transom) onto the rest of the boat were the cables. He made it back to land safely on his own; boat sank. Grin whadda deal!

 

[BWR1953]

Back in 1992 I bought a 150HP motor which had been mounted by some kid onto a 15' bass boat rated to only 90HP.

The reason the kid sold the boat/motor was because the transom and stern of that boat had been cracked and split by the excess power from the 150 outboard.

The max HP isn't just for weight considerations, but for structural reasons too.

On the flip side, I learned that having a boat with less than max power can be unsatisfying. The first (and only) brand new boat that I owned was rated at 75HP but was equipped with a 50HP at the dealership. I definitely should have paid the extra money for the 75. I kept that boat longer than any other that I've owned, but throughout that time I always wished that I'd had the larger motor. There had been times when I simply couldn't get it on plane with a big passenger.

Back to the 150... I'd ridden in a 17' bass boat with a 115HP outboard and it was nice. That boat was rated for 150 but the owner was okay with the 115. However, when my big cousin and I got in the boat with the big owner, that boat could really tell we were there. :lol: Right then, I decided that if possible, that I'd always go with max HP when I could.

So when I bought my 17' bass boat, it had a 115 onboard which I replaced with the 150 before taking delivery. I was VERY happy with that boat! Probably my favorite of all the boats that I've owned so far.

My advice: get the max power on the boat for which it's rated and you'll be happier in the long run.

 

[gm280]

My take on MAX HP is this; Whenever I buy a boat or even an ATV, or the likes, I try to get the max HP engine I can afford up to and including the MAX HP rating allowed. Why, you may ask? Because down the road every engine gets tired. That IS a fact of life! And when that happens I still want to be traveling comfortably without issues. You can always throttle down with MAX HP setups, but you can only throttle up so far if you buy smaller HP setups.

I once own a very nice Bass Boat that had a Tower Of Power inline 6 115HP engine on that 15 foot boat. On good water I could reach 63 MPH. That was fast enough for me. But 99.99% of the time, I cruised along between 35 and 40 MPH and enjoyed it. But if I had to, I could get in a lot quicker is necessary. Just my mindset of HP!