Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Whaler Porpoising?
Posted by louylouy on 04/20/10 - 8:21 AM
#1
My first post so please forgive me if this information is posted elsewhere. I have a Dauntless 15 with a 60 hp Johnson. On my first cruise I noticed the boat was very susceptible to porpoising when changing speeds or power setting. Yes, it can be trimmed to alleviate the problem, but with a slight degradation in speed at the same power setting. Yes, I know that load distribution will affect this problem. I saw a product on Shipshape TV that is ABSOLUTELY the best item I have installed on a Whaler. It solves the porpoising problem for good and adds about 3 mph higher top speed. Before I mention the name, please understand I am not specifically advertising this product, but trying to help fellow Whaler owners enjoy their boat more. Having said that, the product is Smart Tabs. I put the 40# on my boat. All the difference in the world. Made my boat handle like a 17'. Great for increased lateral stability, too. If you have a very fast V hull boat, these will eliminate chine walk at high speeds, too.
Smart tabs are easy to install. Just remember that the farther out from centerline on the transom you put them, the greater their influence on lateral stability is. FORGET motor mounted "Whale tails". Although they will give you slightly better out of the hole jump, they also give you higher drag and a loss in top speed. Since they are on the centerline, their influence on lateral stability is minimal. Smart tabs allow you to trim your engine for almost 0 thrust angle = 100% forward thrust hence higher top speed. These are simply transom shock absorbers, and they make your ride on plane in rough water much smoother. Coming out of the hole - right now and stay on plane at a slower speed. Are they adjustable from the helm - no. Do they need to be - no. You adjust them per the instructions when installed. Fine tune the adjustment once in the water and you are set. Are they better than trimable tabs? I believe so since they absorb shocks unlike adjustables that are fixed in a selected position until moved again.
Smart tabs are much cheaper than adjustables. No wires, no cables, no hydraulic lines, no control panel. What about warranty? Okay, I had a small rip in one of my two year old cylinder boots. Called Nauticus, told them the problem and that I wanted another boot. No deal they said. They just sent me TWO NEW Cylinders for FREE!!! How is that for warranty?
I've put a set on a 9' Avon, and a 21' Caravelle (300 hp, 60+ mph boat) in addition to my Dauntless 15. No complaints or problems. Check them out. If you put them on you will be satisfied. Let us know.
Posted by CES on 04/20/10 - 10:30 AM
#2
Ya, I've heard of the smart tabs and have heard only great things about them.
Thanks for the information and welcome to Whaler Central!
Posted by Joe Kriz on 04/20/10 - 12:39 PM
#3
Yes, we have that link in the "Vendors Web Links" on the left sidebar.
Or, click on the "Site Map" link to view all vendors listed.
http://www.whalercentral.com/infusion...te_map.php
Unfortunately, your post smells heavily of an advertisement.
louylouy wrote:
If you put them on you will be satisfied. Let us know.
Who is "us" ? Sounds like you are part of the company.
So, If you would like to advertise on WhalerCentral,
"Let us know"....
Edited by Joe Kriz on 04/20/10 - 1:03 PM
Posted by DWinter on 04/20/10 - 3:55 PM
#4
Any 15' boat that requires trim tabs has something else going on. weight distribution, trim, something!! I've driven every civilian model whaler built between 2004 and 2009 and never had this issue. I'm not trying to sound like a know it all, but I suspect something isn't right with the boats set-up.
Posted by JohnnyCW on 04/20/10 - 6:34 PM
#5
Joe Kriz wrote:
Unfortunately, your post smells heavily of an advertisement.
louylouy wrote:
If you put them on you will be satisfied. Let us know.
Who is "us" ? Sounds like you are part of the company.
So, If you would like to advertise on WhalerCentral,
"Let us know"....
I originally took
us as being the forum members. Sort of like asking anyone else with experience to report back to the forum for the benefit of others. However I see your point as well Joe.
I've never had porposing issues with my old 13 or my current 17 but I guess there are potentially other benefits as well. Guess I'd need a side by side comparison to know for myself but I'm not gonna be drilling holes in my hull just for a trial.
I think there is a guy advertising a 52mph 13 footer on ebay using them... lol.
Edited by JohnnyCW on 04/20/10 - 6:36 PM
Posted by Tig on 04/20/10 - 6:46 PM
#6
DWinter, I'm with you. No disrespect intended to those that sell or use trim tabs, but I find the acceptance puzzling. It just seems to me that a properly designed and set up boat will run well as is. My dauntless did porpoise easily last year, if I trim up. At the same time it also ran faster that I expected. I look at the porpoising as a tuning puzzle. I want to figure it out. To that end the motor is mounted as per manufacturer instructions which placed the anti-ventilation plate 5/8" below the keel. I think that raising it a notch or two will mellow things out. If not, it still runs fine.
Posted by Joe Kriz on 04/20/10 - 7:01 PM
#7
Tig wrote:
To that end the motor is mounted as per manufacturer instructions which placed the anti-ventilation plate 5/8" below the keel.
Which manufacturer instructions are you referring to?
Whaler or the Engine manufacturer?
The cavitation plate should be just above the water when running the boat on plane.
Any other recommendation on dry land would be just a starting point: So far above the keel or so far below the keel.
The water trail is the final test to get the height of the engine right.
Posted by Tig on 04/20/10 - 7:54 PM
#8
Hi Joe,
It's the instructions from the Honda maintenance guide that I was referring to. I'm traveling so I don't have them on hand, but speaking off the top of my head they went something like this; Measure 20" from the keel to the top of the engine's transom mount. They may have assumed the transom would be 90 degrees to the keel. I did not do the geometry calcs to figure out why but on a Dauntless 15 the anti-vent plate ends up underwater 7/8". I measured and took some decent pics before I moved the engine. If you like I could do a project album on raising the engine and post my observations. It was simpler than I thought using tips I gained here. I went up two notches and the the anti-vent plate is now 5/8" above the keel. All this is in prep to go to an SS prop this summer. I'm moving one step at a time to see what each change does for me.
I agree with the water trial. Last year I had a lot of spray back from the lower end. Sometimes even over the transom. Only once was I able to really trim the motor out. In that case I was at max capacity (850lbs) and 500 of that was in the bow.
Posted by Joe Kriz on 04/20/10 - 8:05 PM
#9
I was just curious as to the manufacturer recommendations.
I'm glad you know that every boat and motor combination may be different and that you must sea trial the boat to get the engine height just right.
A friend of mine has a 1996 Outrage 17' II and no one can sit in the back jump seats without getting completely soaked. Ok on a hot day... :-)
However, he knows the engine is way too low so we are going to raise it up one of these days.
Sure, let us know what you find out and at what the optimum height is for you.
One hole up, two holes up, etc... on the engine bracket mounting holes.
Posted by gilgotes on 04/20/10 - 10:15 PM
#10
Joe Kriz wrote:
Sure, let us know what you find out...
Joe, Pun intended? : )
Mike
Posted by thegage on 04/21/10 - 5:21 AM
#11
I'm always skeptical where a person's first post to a forum is a product endorsement and they claim not to be "specifically advertising this product", especially when the manufacturer already has a link on their site to a WhalerCentral discussion.
John K.
Posted by tedious on 04/23/10 - 6:38 PM
#13
Am I the only one who objects to this on someone's very first (and to date only) post?
Spamboy needs an invitation to take his blatant advertisement elsewhere.
Tim
Posted by mattgeiger on 04/24/10 - 12:24 PM
#14
tedious wrote:
Am I the only one who objects to this on someone's very first (and to date only) post?
Spamboy needs an invitation to take his blatant advertisement elsewhere.
Tim
No. You're not alone. I don't believe anyone missed the fact that this was a marketing pitch. It is garbage like this that can destroy the sanctity of a good forum.
Posted by arthureld on 04/24/10 - 12:57 PM
#15
It is annoying when someone tries to pull the wool over your eyes but there have been a few people claiming to be happy with this product.
We are all trying to dig up info and maybe Nauticus Inc will become a site sponser.
I'm sure that would be helpful to the site.
Edited by arthureld on 04/24/10 - 1:02 PM
Posted by CaptnChris on 04/24/10 - 1:29 PM
#16
DWinter wrote:
Any 15' boat that requires trim tabs has something else going on. weight distribution, trim, something!! I've driven every civilian model whaler built between 2004 and 2009 and never had this issue. I'm not trying to sound like a know it all, but I suspect something isn't right with the boats set-up.
I am inclined to agree with you. A boat that has a porpoising "attitude problem" can most always be easily corrected. Shifting weight properly and motor height is basic.
The right prop is paramount and can most always properly correct the problem. It is also one of the most misunderstood, most important necessities for a boat, thus minimized as relatively insignificant....not the case at all! Tabs have their place, no doubt....for listing issues. Tabs can also create a false sense of fore and aft correction which can be detrimental to performance and economy. When understood and used properly, they are important equipment...but, not for a quick fix. Zero trim angle +(or closely thereto) is where your motor should be at cruise or speed and anything negative of zero and you are are compromising your power with economy suffering along with it. And those "whale tails"? I see them and think, Oh my!!