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View Full Version : Porpoising update


AHudgins
09-04-2005, 10:43 PM
I had mentioned before that I was going to have my hull hooked to fix the porpoising problem on my Maristar 200. After a few trial tests, I got my plastic wedges to actually stayed glued to the bottom of the hull for an entire day. I made the plastic wedges to match how much hook the fiberglass guy said I would need to fix the problem. Think of the wedges like a door stop, except it is only 1/2 tall and it is 6 inches wide. I glued two of the wedges, one on each side of the boat between the chines. Hard to believe, but that was all it took. The boat would plane out at 15 MPH, and the porpoising problem is gone all the way up to full throttle. The harder I pushed the throttle, the more the bow came down (stern went up). I lost about 2 MPH off the top end but that doesn't concern me, I can now barefoot and the boat doesn't buck up and down. I am going to make the wedges a little smaller just to see how little of a hook I will need before I do the actual fiberglass work. I know some of you have had good luck with the trim tabs, I just hate to drill holes in my boat below the water line. I added a tower to my previous boat, and I was sweating bullets when I had to drill all of those holes!!!!

peason
09-04-2005, 11:42 PM
Sounds great - I'm sure after the long weekend more people will look at this thread.

Leroy
09-05-2005, 12:09 AM
Great solution, hard to believe it would cost you 2MPH, are you using pitok or paddle wheel?

erkoehler
09-05-2005, 12:36 AM
If you have pics, that might help to visualize the change made.

AHudgins
09-05-2005, 09:50 AM
By forcing the stern up, and the bow down, it puts more of the hull surface onto the water which will cut down on the top end speed. I will try to get a few pics posted if I can do it without messing up my post, haven't attached any pictures before.

I don't mind cutting down on my top end speed just a little. I have been fighting this porpoising problem since I traded my Prostar for the Maristar two summers ago. Some times I can slalom without a problem, but barefooting is not an option with this boat. Once I put the boat away in October, I will have the fiberglass hooked added since I won't be spending $100 to fill up my tank!!!!!

bigmac
09-05-2005, 10:05 AM
I know some of you have had good luck with the trim tabs, I just hate to drill holes in my boat below the water line. I added a tower to my previous boat, and I was sweating bullets when I had to drill all of those holes!!!!

Understandable. OTOH, permanently adding fiberglass that's non-adjustable and no-going-back would kind of give me the willys. The only hole that goes through the transom is the one for the actuator wire. The bracket and actuator are mounted with SS sheet metal screws and a generous amount of silicone sealant. It's how MasterCraft does it on their new boats (X-30/230VRS) that come with the same trim tab. I also like the idea of being able to retract the plate fully so I don't lose anything at the top end. Of course, it's easier for me to say since I don't have a porpoising problem - the reasons I'd install the thing on my boat are different than the reasons you need the change...

gregg
09-06-2005, 06:45 PM
Understandable. OTOH, permanently adding fiberglass that's non-adjustable and no-going-back would kind of give me the willys. The only hole that goes through the transom is the one for the actuator wire. The bracket and actuator are mounted with SS sheet metal screws and a generous amount of silicone sealant. It's how MasterCraft does it on their new boats (X-30/230VRS) that come with the same trim tab. I also like the idea of being able to retract the plate fully so I don't lose anything at the top end. Of course, it's easier for me to say since I don't have a porpoising problem - the reasons I'd install the thing on my boat are different than the reasons you need the change...

Right on bigmac. The more you drop the wake tab the more top end it kills. The more I use this thing the better I like it. Before, to get on plane to smooth out choppy water was 25 or so mph. Now plane is less than 20 with the tab all the way down. On calm water days it takes only a very slight movement of the tab when porpoising begins, but no affect on top speed. In my opinion if adding hook was going to cost anywhere close to 500.00 I would spend the extra and get the tab. I love the way you can trim the boat regardless where your passenger are sitting.

love2fly
09-06-2005, 09:16 PM
I would be interested in what you are doing and seeing some pictures. I did notice my 200 was doing the same but was not sure if was me just loading the boat incorectly.

AHudgins
09-06-2005, 10:04 PM
I am pretty sure I will go with the hull hooking over the trim tab, I went from a top end of 45 to 43 with the 1/2 inch wedges (I actually picked up 1 or 2 MPH with the OJ XMP prop). I plan to shave the wedges down a little at a time to see what is the minimum I need to stop the porpoising. Just like with the trim tabs, I couldn't believe how fast my 200 got on plane, and is was such a relief to hit barefoot speed and have the boat actually drive like a MasterCraft!!! I will do a lot of testing AND thinking before I make my final decision, but my 16 year old son has a hard enough maintaining the boat speed while he is playing the stereo and talking to his girlfriend. And my wife, you can forget it Ha Ha.

I only get to ski on the weekends, but I will see if I can run to the lake during the week and get some pictures. All of the input has been very helpful. If it hadn't been for the posts about using duct tape and trim tabs, I never would have thought about using the plastic wedges.