How much power do I need?

[hostage]

I didn't know where to put this, since this isn't a repair/maintenance question. I am wanting to buy an open bow for water sports and cruising. I am looking at having 4-6 adults on the boat with one of them skiing or tubing. Do you guys have any suggestions on how much power I would need? I was looking at 2 boats, one with a 3L i/o and another one with a 4.3L i/o. Is a 4.3L more along the lines of what I need? I am not crazy about power, just want something that meets my needs.

Thanks,
Hostage

 

[cr2k]

Re: How much power do I need?

In the scenario you listed the 3.0 would be marginal for skiing in a boat that would hold that many people.

If you have too much power you can always throttle back.
If you lack power you can never throttle up.

 

[26aftcab454]

Re: How much power do I need?

^^^^^^ exactly what he said

 

[Mark42]

Re: How much power do I need?

There are very few bow riders in the mid size market, 18 - 22 ft, that are over powered. Best to go with the highest hp available, it comes in handy when the boat is loaded and you want to tow a tube, etc.

 

[mruniverse1973]

Re: How much power do I need?

No less than 300hp the first time your loaded down and dont pop up on plane you will kick yourself. I made this mistake on my first boat a 18' crownline with a 4.3. Also if your boat is rated for 8 then 4 is the comfort range. My 23' crownline is rated at 12 I cant even count that many spots to sit. 6 is perfect on it.

 

[nitsuj]

Re: How much power do I need?

I completely disagree with that. For a smaller boat, 300 is nice, but it's far away from what I'd call the only way to go. Heck, my first boat had 115hp and it would pull 2 skiers no problem. A 4.3 is a good strong running engine that will propel a bow rider to a respectable speed and it will pop right up, even loaded. If it won't, you need to examine your prop selection. My old 67 Johnson is a big heavy pig with a Buick 300ci V8, maybe 200 HP max. And it gets up on plane quickly even with 4 people on board.

 

[haulnazz15]

Re: How much power do I need?

I also disagree that you need 300HP+. My 76 20' runabout pops me up (210lbs) on slolam with 4-5 200lbs guys aboard with no problem. It had 233HP new, but likely much closer to 200HP. While I won't argue that more HP is always desireable, most every 18-22ft runabout has less than 300HP. Hell the 5.7L was only rated at 260hp and was used in the majority of boats as the "premium" powerplant until the past decade when they started making Bravo outdrives more popular on runabouts.

I will say this once: get a v8. I have been on many boats, some with 3.0L, some with 4.3L, and some with v8's. The V8's always have the power to get the work done when the boat is loaded down, the 4.3L can do it, but it will struggle when the boat is loaded. The 3.0L will suffice for the occassional heavy skier, but it isn't a good option if you plan on doing much more than cruising or towing small children.

 

[wca_tim]

Re: How much power do I need?

horsepower is like sex... too much is never enough.

I would err on the high side... and in a larger bowrider, want a big block... in an 18 ish boat, a 350, and at a minimum a 4.3....

 

[mruniverse1973]

Re: How much power do I need?

Prop selection is a big part of it but the more hp you get the closer you are to the best of both worlds. Hole shot and top end I run a 4 blade 21 pitch ss vensura have great hole shot and decent top end around 55 at 4600 rpm. All of my kids love wakeboading tubing and so do I so hole shot is somewhat important to me.

 

[mike343]

Re: How much power do I need?

Shouldn't someone ask how big (weight) the boat is? Six adults and a 20ft boat comes close to a 5.0.

 

[cr2k]

Re: How much power do I need?

Well the Crownline line of boats are well built but with that comes the weight. I would want a 5.7 min for a 20+ Crownline.

 

[Yellow Yota]

Re: How much power do I need?

After looking at several boats in the 20' range that had either the carb'd 5.0 (220 HP) or the EFI 5.0 (270HP), I'm very glad I held out for more. I found a 21' Rinker RX1 with the 350 MAG MPI engine. It's 300 HP or so. It only has a 17 pitch prop from the factory, but it will darn near pull a house out of the water. Sure, top speed is only 48 on the GPS, but it'll still do that with 7 people on board. Pulling anyone out of the water is effortless, and during normal cruising, you're barely in the throttle.

I am so glad I held out for the 5.7, as I was afraid of "outgrowing" a lesser powered boat. I imagine this one will last me for a while!

 

[hostage]

Re: How much power do I need?

Good information, I should also mention that I can only tow a max of 4500 lbs and don't really want to spend more than $5k.

 

[mruniverse1973]

Re: How much power do I need?

I would have to say your best bet would be a 18' with 4.3 mercruiser should be able to find one with 190 hp.

 

[nitsuj]

Re: How much power do I need?

Get the 4.3. It will be cheaper to buy, cheaper to operate and since it's a first boat, if (when) you want to move up, you'll have a better idea of what your needs are. Just one mans opinion.

 

[elkhunter338]

Re: How much power do I need?

I run a 21 foot alum cuddy cabine with a 3.0 in it. with 4 pobs at sea level I only get 26mph at 3800 rpms, I can change the prop and I still get 26 mph ish and just gain rpms. my boat weight is around 4500lbs including trailer so boat I guess is around 3500ish. the 3.0 makes a great fishing boat, cruise at 20mph. I would guess not good for skiing. I do not ski. I would go with the 4.3, or get theguy to let you try the 3.0 and see if it runs good enough.

 

[83Evinrude]

Re: How much power do I need?

Up to 18' you will probably be happy with a 4.3 V6, 19-21' I would get a V8, over 21' a big V8.

 

[tawood]

Re: How much power do I need?

I always scratch my head when I see these type of posts, only because my 19 footer has a 3.0L, will do 40-45 mph (depending whether it is just me or full capacity), and WILL pull skiers with 6 people in the boat, no problem. Maybe my family averaging of 170 pounders is light these days, I don't know.
I think if they made a boat this size with a 700 hp V12, nearly everyone on here would say, "If you are pulling a kneeboard, you absolutely NEED the v12!!!"

 

[RL Gman]

Re: How much power do I need?

I always scratch my head when I see these type of posts, only because my 19 footer has a 3.0L, will do 40-45 mph (depending whether it is just me or full capacity), and WILL pull skiers with 6 people in the boat, no problem. Maybe my family averaging of 170 pounders is light these days, I don't know.
I think if they made a boat this size with a 700 hp V12, nearly everyone on here would say, "If you are pulling a kneeboard, you absolutely NEED the v12!!!"

I completely aggree here!

Now, I've been boating for a while, and I love to grab more HP on each new boat. It's an interesting dichotomy of people; new boaters just trying to get a reasonable boat that gets them on the water, and the experienced, that just want to keep going faster, harder etc etc.

I compare it to my car...I got a BMW 335i. Now thats a twin turbo v6. Probably one of the fastest little stock cars on the road. And when you open up the turbos, it can feel down right crazy. But after I've driven that for a while, I'm already feeling like increasing the tubos, or just upgrading to the M3...While, someone who had never driven anything like that would be completely happy with the 330 that is a strong v6 that has more than the "normal" power!

Back to point: I would pick the 4.3 just because you already plan on takin several adults, but both will serve your purpose!

 

[tawood]

Re: How much power do I need?

Funny RL Gman, but I did the "more power" thing for years, and now I'm going the other way: my boat is the smallest horsepower engine I've ever had, my cars keep getting less power, even my motorcycles are getting less (and slower)....must be my age is showing!!!!