Bass Boat Max HP rating

[SpinnerBait_Nut]

Re: Bass Boat Max HP rating

is putting high compression heads and pistons to squeeze out all the power you can under this catagory.. my dad had a yammy 175 that prob put out around 250hp after it was modified this was on an allison bass boat..

Depends on what size Allison it is.
Like Gambler and a couple others, they are in a league of their own.

 

[CATransplant]

Re: Bass Boat Max HP rating

175 max is 175 max. Doesn't matter if you added a supercharger or bought a bigger motor.
Let me put it this way. You can take your boat and kids/grandkids on one of 2 lakes. One lake all boaters have the proper hp rating on their boats. The other lake has all boaters who overpowered their boats to get more speed than the boat was intended to use safely. Which lake would you trust to take your kids/grandkids out for a nice safe day on the lake?

Sadly, there are a lot of folks who don't care about yours or anyone else's grandchildren or children. It's all about how fast they can go and how much noise they can make. They're the same ones who think it's amusing to make a sharp turn in their jet boat right beside your 12' fishing boat 50' from the shoreline. "Whoa, dude! We really soaked that geezer, huh?" That actually happened to me once. Fortunately, the lake patrol was nearby. The boys not only got busted for unsafe boating, they got to take a ride in the nice cop car because they were all too drunk to drive the boat.

We all have to keep a weather eye out for the irresponsible boaters. They're on every lake. It's too darned bad, really. Of course, one of these days, someone in an overpowered bass boat will be running at about 65-70mph down the lake on a windy day and cross the wake of some wakeboarding boat with half a ton of water in the stern to make a huge wake. The bass boat will kite itself and end up upside down, and the wakeboat driver won't even notice. Then, the quiet folks with normal boats will motor over and see if they can help the guy who was ejected from his boat before it flipped. We'll feel really bad for the guy, and will do everything we can to save his life.

 

[xxturbowesxx]

Re: Bass Boat Max HP rating

Depends on what size Allison it is.
Like Gambler and a couple others, they are in a league of their own.

it was a 18'... my dad had many performance boats including a triad river rocket with a 2.5 racing merc.. notice on the 2.5 merc nowhere does it advertise or state how much hp the engine has.. my dad used to bass fish for a living and while sponsored was given fast boats and got bit by the fast bug.. he would later get into recreational drag racing and he is probably one of the safest boaters i know..he wasnt following close to boaters he didnt drink and drive he would find the most remote piece of water and have fun..
as a kid there was a strict speed limit of 55 set by my parents and i wasnt allowed to ride in the boat if my dad was going to go faster than that..

the go fast boat crowd tend to dislike wakes and keep to themselves..the overpowered boats just like any other boat is only as safe as the operator.. to answer one posters question about a lake full of overpowered boats and a lake of recreation boats which would i like to be on? i would choose the overpowered lake because these guys are avid boaters and builders and know what they are doing..id rather share the road with race car drivers than your average joe.. i grew up around these people and trust me you would rather have them around than a jet flea infested lake with recreational boaters pulling tubers in circles at 35mph in the channel..the guy in the jetboat who soaked you was a moron same guy different boat and hes still a moron..just a conflicting opinion not necessarily right but its mine..

 

[alamosaddles]

Re: Bass Boat Max HP rating

Yes, he did ask that. The manufacturer says that it's unsafe by putting the Maximum HP rating on the boat. How did they determine that? Well, they built the boat, so they determined it via their engineering and design.

Thats a very unrealistic view. Example....Your local county or municipality etc. engineered a road near your home. They then determine the posted speed for that road. You know full well that the posted speed is not based on what the road can safely handle or allow. It's based on a multitude of factors. But you and everyone else knows that just because they built and engineered that road, the max posted speed limit of "x" is not necesarily the fastest one can safely travel on that road.

When an elevator says 1200lbs limit, you know if you load 1225lbs it's not going to come crashing down the shaft. If your tires are rated for 125mph, you know at 127mph they aren't going to disintegrate. Pretty much everything has a large safety buffer built in.

Personally, I rely on the manufacture to know their boat and its capabilities. My current boat has a hp limit of 10. I have a 15hp outboard sitting in the garage, and a 6hp on the boat. Why? Because the manufacturer says that the boat is only rated for 10 hp. I figure they built the boat, so they must know its limits.

I can tell you factually, that the maximum number of passengers, maximum weight limit allowed and maximum horsepower rating for a vessel is NOT based only on what that particular vessel can safely handle, but instead a formula is utilized to arrive at these numbers. This formula takes a number of variables into account, and gives a final set of limits which have a large considerable safety buffer built in before any safety breaches are even close to being broached.

Additionally, the government has a role in some of these formulas and limit determinations.

Before I get slammed for not knowing what I am talking about, my eldest brother was an engineer with Donzi for 12 years.

 

[2kwik4u]

Re: Bass Boat Max HP rating

175 max is 175 max. Doesn't matter if you added a supercharger or bought a bigger motor.
Let me put it this way. You can take your boat and kids/grandkids on one of 2 lakes. One lake all boaters have the proper hp rating on their boats. The other lake has all boaters who overpowered their boats to get more speed than the boat was intended to use safely. Which lake would you trust to take your kids/grandkids out for a nice safe day on the lake?

The one with the least number of idiots behind the wheel would be my choice.

If "max hp" is such a big effing deal then why don't car manufacturers do the same thing? I would think that the shear number of cars, and drivers would lead to a greater liability. Having driven twin turbo V8 SUV's on the street, as well as underpowered 4cyl hybrids, I'll gladly take the former over the later. As a mechanical engineer I feel qualified in saying that the max rating is most likely determined by lawyers and accountants than the engineering staff. I know if I was designing a boat I'd have a safety factor built into the transom strength calcs, and then take 50hp off that and hand that figure to the marketing dept to make a placard that listed max HP rating. They would then get lawyer approval, and management approval, and a list of other approvals that would probably bring it down a bit further.

Seriously, you guys are all bent out of shape over something that is so damn trivial it's borderline hilarious. If he didn't ask, went and overpowered his boat, and then went to the lake I seriously doubt any single one of you could pick his boat out of the crowd as being unsafe. Especially if the only thing that has changed is the number on the back of the motor housing! I'm positive you can't tell the difference between 65mph and 75mph visually without a radar gun.

I say let him do it. If he feels the boat is safe, so be it, if he puts it on there and it's got so much torque it rips the transom off the first time he firewalls the throttle he'll have learned his lesson. I think I'd rather rally against the endless stream of idiots drinking on the water, having no courtesy in general, and a lack of ability to learn any better, than rally against this guy.

Seriously, go find something better to do!

And to answer his initial question.....It will probably be fine with that 200hp on there. There really is only one way to find out! However it's an expensive experiment!

 

[Booberdoo]

Re: Bass Boat Max HP rating

I was wondering something about this topic...

First, I do not indorse exceeding manufacturer's HP ratings. If something were to happen like hitting a swimmer or something, what could have been an accident now could be prosecuted as negligence. Not worth the risk in my opinion.

What I was wondering about, aside from the legalities is why so many people consider an overpowered O/B so horrible dangerous while at the same time an I/O has no max rating...I could plop a 1500 HP blown, alcohol injected big block in a 14' jet boat and nobody would say a thing... I just don't get it.

I am a motorhead, I build drag and circle track engines. I personally drive a 600 HP Firebird on the streets (not much with the gas prices now), my jeep is capable of low 14 to high 13 second passes and I have never been ticketed or had an accident (we won't mention totaling two cars in a friend' driveway). Anyways, its not the high HP cars on the road that bothers me, its the kids in their little imports with those huge exhaust tips that scare me; those kids exceed the safety limit of their cars regularly. I guess it would be the same on the water. The reckless are dangerous whether in a Scarab or a rowboat.

Does anyone know what is typically used for a boats safety factor? Everything has one (except maybe Walmart products). Off the top of my head somewhere around 1.5 seems appropriate, which would make this bass boat capable of taking 225 HP before breaching of the structural integrity of the transom/hull becomes inherent. That seems in the ballpark to me. I see no point in doing it though, as those things are fast enough as it is.

So, what exactly is everyone's personal vendetta against someone exceeding the HP rating? in this example 50 extra HP isn't going to make the boat anymore dangerous than it already is. To me it seems like the same thing as outlawing .50 BMG rifles; like a .22 is any less dangerous... It is all in the hands of the operator, I've seen idiots on peddle boats that were dangerous...

Disclaimer: I do not endorse exceeding manufacturer ratings due to the legalities involved and unless you actually designed the boat you have no way of knowing the fail point of the structure.

I was just curious as I see quite a few threads where someone wanted to do it and was beat down for the idea.

 

[CATransplant]

Re: Bass Boat Max HP rating

Nobody's beating anyone down here. Someone comes on and asks for opinions about overpowering a boat. Others give their opinions. They point out many of the same things you do, like increased liability and decreased safety margins.

Since none of us is in the business of enforcing such things, we're just offering our opinions. Anyone is free to accept those opinions or reject them. There it is.

 

[haskindm]

Re: Bass Boat Max HP rating

You may install any size motor on your boat that you wish - however, if the state in which you are operating has adopted the NASBLA standards you may not legally operate the boat in that state. The exact wording of the standard is:
(2) No person shall operate any vessel described in subsection 2-1 when said vessel exceeds:
(a) The maximum weight capacity, or
(b) The maximum persons capacity, or
(c) The maximum horsepower, or
(d) The capacity limits as identified on the ?Capacity Label,? or by calculations provided in 33 C.F.R., Part 183, subparts C and D.

So whether or not your boat can "handle" the power or whether the standards have a "safety factor" built in is beside the point. In most states your boat will be in violation and if boarded for any reason you will at least be fined or perhaps have your boat registration revoked. You can "second guess" the manufacturer, but be aware of the consequences.

 

[Booberdoo]

Re: Bass Boat Max HP rating

You may install any size motor on your boat that you wish - however, if the state in which you are operating has adopted the NASBLA standards you may not legally operate the boat in that state. The exact wording of the standard is:
(2) No person shall operate any vessel described in subsection 2-1 when said vessel exceeds:
(a) The maximum weight capacity, or
(b) The maximum persons capacity, or
(c) The maximum horsepower, or
(d) The capacity limits as identified on the ?Capacity Label,? or by calculations provided in 33 C.F.R., Part 183, subparts C and D.

So whether or not your boat can "handle" the power or whether the standards have a "safety factor" built in is beside the point. In most states your boat will be in violation and if boarded for any reason you will at least be fined or perhaps have your boat registration revoked. You can "second guess" the manufacturer, but be aware of the consequences.

Maybe I didn't word myself well enough, but as a practicing Structural Engineer (I do buildings, not boats), I am well aware of the hazards of "second guessing" the manufacturer and I don't condone it.

My thoughts were more on the lines of why people feel so strongly against an overpowered O/B but really have nothing to say about an overpowerd I/O. It seems that a lot of people feel the overpowered O/B makes for a dangerous situation in regards to the safety of others where evidently the overpowered I/O doesn't (or maybe it just seems that way).

That was what I was wondering about, I sure am not trying to suggest that it is ok to overpower anything unless for specific reasons like sanctioned racing or the like, and then one must know exactly what they are doing before they do it.

 

[CATransplant]

Re: Bass Boat Max HP rating

I don't read the I/O section, and I don't think I've ever noticed anyone questioning whether they should overpower an I/O boat. I've never owned one, so I don't know what the capacity tag says on them. Does it not have a horsepower maximum?

But, when it comes to outboard boats, there is a steady stream of posts where someone is asking if they can put an 18 hp outboard on a boat rated for 10 hp, and the like. In this case it was a 200 hp outboard on a boat rated for 150 hp.

Heck, I have a 12 foot aluminum semi-V. It's labeled limit is 10 hp. Yet, I could clamp on anything with clamps and a short shaft. I'm sure if I put my old 35hp Johnson on there it'd go like stink. Sure wouldn't be safe, though. Even with a 10 hp, it takes a careful hand in turns not to get the inside gunwale too close to the water for comfort. I wouldn't put a 15 on it, since it'd be useless to me, and I just fish out of that boat. Now, if I added a console to it, then I'd be comfy with a 15 on it. With a console, it probably would be rated for 15.

If they ask, folks are going to respond. Heck, if someone asked if they should put a 5.4 liter engine in some 17' Wellcraft to replace the 3.0 liter Mercruiser in it, I'd answer that it wasn't safe, since the boat wasn't built to accomodate such a thing. But, I've never seen that question, probably because the cost of such a conversion would be prohibitive and the hull doesn't lend itself to such an installation.

Outboards are different. You just clamp that big outboard on or bolt it up and it's there. That's awfully tempting to a lot of folks who may well not have the sense not to do it. So, there are some of us here who point out the folly of doing so, for safety and legal reasons.

But, as I said before, we can't stop them from doing it. We can just advise against it and give the reasons why. There's a big difference.

 

[Booberdoo]

Re: Bass Boat Max HP rating

I don't read the I/O section, and I don't think I've ever noticed anyone questioning whether they should overpower an I/O boat. I've never owned one, so I don't know what the capacity tag says on them. Does it not have a horsepower maximum?

I was reading this: http://files.dnr.state.mn.us/education_safety/safety/boatwater/backyardboatbuilders.pdf

On page two it states that there is no max HP regulation for I/O which is why I was wondering, but I do like your explanation of how the added power could cause an unsafe situation as far as handling goes. That makes perfect, logical sense. It would not be fun to overpower in a turn and wind up on your side...

That is what I like; clear and concise answers to questions. Thanks.

 

[CATransplant]

Re: Bass Boat Max HP rating

That's a great web page. I've bookmarked it. Oddly enough, though, it has my 12' aluminum boat rated for 15 hp, while the manufacturer sets it at 10 hp. I think the manufacturer's rating is better, based on my experience with the boat. The weight rating is right on the money.

But, referring to bass boats, which was the original topic, I've ridden in a bunch of them, almost all powered to their max hp. At least half had serious chine-walking behavior when run wide open, unless the water was glass-smooth. A couple of them scared the heck out of me.

The problem may have been poor setup or trim. However, I'd not ride in one that had an overpower setup.

The other problem is that not everyone is a capable driver. In fact, that's the biggest concern, in my opinion. Combining an inexperienced operator with an overpowered boat seems to me to be a serious accident waiting to happen.

Myself, I have no desire for a high-performance boat. That's just not my deal, but I understand that a lot of folks do. The manufacturers, I think, set limits based on safe limits and average operators. They don't want to be sued if someone crashes due to an unstable, overpowered boat. I don't want folks to have accidents based on unstable, overpowered boats, either, because I may be sharing the water when such an accident occurs.

So, when someone asks whether they should overpower, my answer is always no.

 

[Booberdoo]

Re: Bass Boat Max HP rating

I agree with you on the safety/inexperience issue wholey, and I also agree that too much power in the wrong hands is a disaster waiting to happen. I don't quite understand why HP limits are not set for I/O's though. I know that some lakes restrict all boats to a certain HP. Of course, there was a guy at a place I used to work that managed to roll his Yugo in the parking lot, talk about underpowered AND dangerous; I can only imagine him with a Corvette or something!

Maybe it has something to do with the balance of the boat? With the engine inboard it seems as if the CG would be lower and more centered thus making the boat more stable even with greater power...

Just thinking out loud.

 

[CATransplant]

Re: Bass Boat Max HP rating

I'm not sure either about the lack of horsepower limits for inboards. From what I've seen with manufactured boats, they don't seem overpowered, for the most part. There are the racing boats and the go-fast boats, but most seem to be fairly conservative in their power.

Could be the inboard thing does affect the center of balance enough, or maybe it's just that it's sort of impossible to judge horsepower for that type of installation. I just don't know.

I do know that the wakeboarding boat that went by me on Wednesday sure tested the abilities of my little boat to deal with waves. After it passed, I had to fire up the engine, drag my mushroom anchor, and get faced into that wake. It wasn't overpowered, but it sure was heavy in the back and threw a monster wake.

I guess that's by design, and everyone has a right to be on the lake, but I've learned not to take those particular wakes broadside. But, that's another subject.

 

[xxturbowesxx]

Re: Bass Boat Max HP rating

Thats a very unrealistic view. Example....Your local county or municipality etc. engineered a road near your home. They then determine the posted speed for that road. You know full well that the posted speed is not based on what the road can safely handle or allow. It's based on a multitude of factors. But you and everyone else knows that just because they built and engineered that road, the max posted speed limit of "x" is not necesarily the fastest one can safely travel on that road.

When an elevator says 1200lbs limit, you know if you load 1225lbs it's not going to come crashing down the shaft. If your tires are rated for 125mph, you know at 127mph they aren't going to disintegrate. Pretty much everything has a large safety buffer built in.



I can tell you factually, that the maximum number of passengers, maximum weight limit allowed and maximum horsepower rating for a vessel is NOT based only on what that particular vessel can safely handle, but instead a formula is utilized to arrive at these numbers. This formula takes a number of variables into account, and gives a final set of limits which have a large considerable safety buffer built in before any safety breaches are even close to being broached.

Additionally, the government has a role in some of these formulas and limit determinations.

Before I get slammed for not knowing what I am talking about, my eldest brother was an engineer with Donzi for 12 years.

oem manufacturers make cars with a certain hp but theres a billion dollar industry in modifiing your engine to have more power than the car was designed for.. so you must label all these people as criminals as well.. your truck came with 30" tires but you decided to lift it and add 35"s once again is your vehicle as safe as it was before.. no but id hope you would have to common sense to not go flying around a corner..so why are the regulations for boats so strict you can build a street legal 1000hp car but if you power a boat 25hp more than whats stated you are breaking the law..and statistically im sure there are more morons on the road than the water..an elevator has no relation to overpowering a boat now if we are talking about the weight capacity of a boat i have no arguement i just dont see what your trying to get across.. i understand that the ratings take in a safety buffer im just saying its a very large buffer whats the real difference between a 150 and a 175..4mph?your on the lake and guy #1 is legal running a 150hp bass boat 65mph in traffic on the lake but hes legal meanwhile guy 2 has a 175 cruising and being a safe operator so where do you draw the line.. just how i feel..

 

[Booberdoo]

Re: Bass Boat Max HP rating

oem manufacturers make cars with a certain hp but theres a billion dollar industry in modifiing your engine to have more power than the car was designed for.. so you must label all these people as criminals as well.. your truck came with 30" tires but you decided to lift it and add 35"s once again is your vehicle as safe as it was before.. no but id hope you would have to common sense to not go flying around a corner..so why are the regulations for boats so strict you can build a street legal 1000hp car but if you power a boat 25hp more than whats stated you are breaking the law..and statistically im sure there are more morons on the road than the water..an elevator has no relation to overpowering a boat now if we are talking about the weight capacity of a boat i have no arguement i just dont see what your trying to get across.. i understand that the ratings take in a safety buffer im just saying its a very large buffer whats the real difference between a 150 and a 175..4mph? so where do you draw the line.. just how i feel..

The way I picture it (or at least part of it) is that when you crank your O/B to lock, the propeler angle is such that it forces the boat to lean. The hull design creates resistance that counters the force of the prop, so if you overpower your boat the force of the prop may overcome the resistance of the hull causing it to go completely over.

I haven't drawn this up or run any calcs on it, this is just my thinking out loud.

 

[haskindm]

Re: Bass Boat Max HP rating

In an I/O Boat the weight of the engine, as well as the torque and thrust of the engine are distributed over the transom and stringers. In an outboard, all of these stresses are concentrated right on the transom. I would think that the ability of the transom to handle these stresses is more of a concern than the few miles per hour additional speed that you would get from overpowering the boat.

 

[xxturbowesxx]

Re: Bass Boat Max HP rating

if you turn lock to lock you might be asking for it.. i dont treat my boat that way and its not overpowered..

 

[CATransplant]

Re: Bass Boat Max HP rating

I think you have it, there. It may well be a strength of materials issue on some boats.

 

[Booberdoo]

Re: Bass Boat Max HP rating

In an I/O Boat the weight of the engine, as well as the torque and thrust of the engine are distributed over the transom and stringers. In an outboard, all of these stresses are concentrated right on the transom. I would think that the ability of the transom to handle these stresses is more of a concern than the few miles per hour additional speed that you would get from overpowering the boat.

I understand that the thrust forces in an I/O are spread out through the boat, but the drive is still out back and the prop still turns causing a rotational force on the back of the boat. So why can you run so much more power than that of an O/B without dumping the boat on an extreme full throttle maneuver?

BTW: I don't crank mine to lock either, but some do just to scare their passengers...

I personally find this kind of interesting, and if an answer can be found and verified then the next time someone asks if they can put their Mercruiser 350 on their inflatable we will all have a better reason not to than just "because the tag says not too".