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Old     (151)      Join Date: Jun 2008       07-08-2008, 6:16 PM Reply   
Any engineer types have time to explain how exactly the wedge works? Like what the water does to the wedge, the wedge does to the boat, and that does to the wake.

Please please please I am not trying to start a who likes/dislikes the wedge post.

If its possible I am curious what differences the size and shape of the wedge would make if it was something other than the factory design.
Old     (texasissippi)      Join Date: Feb 2008       07-08-2008, 6:17 PM Reply   
the wedge will screw your boat up...

no i love it, it just pulls the back end of the boat down. i just happened to hit an underwater stump this weekend with our wedge and it ripped the whole back end of the boat off...

Old     (trace)      Join Date: Feb 2002       07-08-2008, 6:37 PM Reply   
Sure it did, Justin.

It is a hydrofoil - acts like an airplane wing in the water. It directs the passing water upward, which in turn creates downward reaction force on the Wedge. Water is much more dense than air, so the wing doesn't have to be nearly as large to produce a lot of force.
Old     (05mobiuslsv)      Join Date: Apr 2006       07-08-2008, 7:55 PM Reply   
Justin give me a break. I would believe it ripped the whole wedge off, quit running over crap it's hardly the wedge's fault.

Nice description trace..
Old     (26lacefield)      Join Date: Aug 2006       07-08-2008, 8:16 PM Reply   
not saying that they will break off but i'm just wondering what'll happen to the boats in after they've been on there for 15 plus years. the fiberglass will weaken over time(probably not much) and it'll just be crazy to see if they hold in place still.
Old     (swab791)      Join Date: Mar 2005       07-08-2008, 8:23 PM Reply   
Here is your physics lesson for the day
Old     (greatdane)      Join Date: Feb 2001       07-08-2008, 9:05 PM Reply   
Its a waterfoil which is similar to an airfoil but for water. And, Trace is right, since water is more dense, it take less of a "wing" to create the same "vertical" force.
Old     (trace)      Join Date: Feb 2002       07-09-2008, 5:36 AM Reply   
Give it a rest, TK. We all know your motives, and we've all seen that thread. Got any other examples, or is it still just that one guy?
Old     (05mobiuslsv)      Join Date: Apr 2006       07-09-2008, 6:06 AM Reply   
TK you're so predictable. Did you guys get all those creaks, rattles, and shakes figured out on those MC's?
Old     (waterfreak)      Join Date: Jul 2007       07-09-2008, 6:25 AM Reply   
What was the outcome of that does anyone know? First time I saw that thread and there are several examples on there of serious hull damage from wedge.... not just one guy.
Old     (highdyner)      Join Date: Oct 2006       07-09-2008, 6:30 AM Reply   
Actually, I believe the correct term would be hydrodynamics......not physics...
Old     (roverjohn)      Join Date: Dec 2007       07-09-2008, 7:44 AM Reply   
Does anyone know what happened with Greg's battle with BU? I personally thought his demands were a bit silly but I'm interested if he ever got anything from the OEM.
Old     (texasissippi)      Join Date: Feb 2008       07-09-2008, 8:08 AM Reply   
lol - ill try to get a pic of it up... we have a hole in the rear of our boat about 20 inches wide and about 12 inches tall... it didnt rip the WHOLE back end of our boat off, but it sure did a number to it.

the stump was COMPLETELY under water. it was on a river my fam has had a house on for over 30 year.. we know where the stumps are, but we had to swerve out of our normal path to avoid a 4th of july TOURON power turning right in front of us....

oh well
Old     (trace)      Join Date: Feb 2002       07-09-2008, 8:58 AM Reply   
Please post pics, justin. Your boat will make a total of 3 that I've heard of now.

I don't have the Wedge on my VLX, but I do think it's a great innovation. Yes, it probably makes your boat slightly more prone to damage from underwater objects, but if you hit stuff in the water at any speed, serious damage is going to occur, and that is what insurance is for (which Greg did not apparently have - hence his attempts to have Malibu cover the damage). I'm honestly pretty surprised that Malibu has not come up with a shear pin design by now, though, considering the bad publicity from these few events over the years.
Old     (sippi)      Join Date: Dec 2007       07-09-2008, 9:15 AM Reply   
I have been thinkin about this for a while and I've been wondering something...the shear pin sounds like the fix in theory, but I'm thinkin that you have to have a shear pin with an exact load capacity to where it would release it something was hit. the wedge itself has so much force being applied to it as is (otherwise it wouldn't work) if you put a shear pin in wouldn't it break free from the force of normal riding speed or if you went over a roller? just a thought.

by the way doesn't the powerwedge release if something hits it?
Old     (jbarber3orange)      Join Date: Aug 2007       07-09-2008, 9:41 AM Reply   
Are there more issues with the manual wedge or the power wedge? Or both? just wondering
Old     (tampawake)      Join Date: Mar 2008       07-09-2008, 10:12 AM Reply   
Not sure why BU does not abandon the wedge and either build a new hull or figure out a way to gain more ballast. Just hear enough nightmare stories about them being ripped off etc. This is not a bu bash at all. Freaking GREAT boats. Just wonder if there is more to gain by changing something else to gain the same result.
Old     (rallyart)      Join Date: Nov 2006       07-09-2008, 10:18 AM Reply   
Well Chris, at least you know that trace, GD, and nu bu actually read your post and gave you real information.
Old     (spherren)      Join Date: Aug 2005       07-09-2008, 10:24 AM Reply   
My question is, if it is ripping off the wedge, then it should damage the prop and shaft right?
Old     (liquidmx)      Join Date: Jun 2005       07-09-2008, 12:45 PM Reply   
Exactly scooter... which most people FAIL to mention. Anyone who has actually looked at a wedge underneath the boat out of the water would agree. The ONLY way you could rip a wedge off without any other damage to the drive line would be to hit one end or the other within a 1" area outside the prop. Even then I doubt it would do much damage as the wedge would likely shear the bolts and twist around (like they already do from time to time).
Old     (big_brandon)      Join Date: Dec 2005       07-09-2008, 3:04 PM Reply   
Here you go boys, have fun.....

Old     (big_brandon)      Join Date: Dec 2005       07-09-2008, 3:05 PM Reply   
Or how about this one??????

Old     (longhornfan)      Join Date: Oct 2005       07-09-2008, 3:32 PM Reply   
Brandon. In your first pic it looks like the rudder took some pretty serious damage too. Or maybe it's just a wierd angle.
Old     (fletch_tx)      Join Date: Aug 2003       07-09-2008, 3:57 PM Reply   
I have a Malibu myself, so this isn't a hate post. Here in Austin...the areas that we ride have a lot of rocks. When the water starts to drop as the summer goes on....these rocks usually claim a few boats each season. I've actually destroyed the underwater gear on my old Mastercraft twice...and I mean DESTROYED! There was very little gel coat damage each time....the second time it was taking on water very slowly, and that's because the rudder typically shears off, and the prop is mangled...basically the boat practically slides over the obstacle. The problem with the wedge is that it's attached to the lower part of the transom and anything that the prop/driveshaft/rudder area hits or slides over will also catch on the large surface area of the wedge and will likely yank itself out of the hull where it's bracket is attached....possibly creating a large hole like pictured above.

That said....I love my 23lsv, and I'll continue to use my wedge. I'll just be a little more careful and make sure my insurannce is always renewed on time! :-)
Old     (adam_balon)      Join Date: Jul 2003       07-09-2008, 4:25 PM Reply   
pros dont use the wedge they use ballast. alot of ballast.
Old     (tinytdubb)      Join Date: Jul 2007       07-09-2008, 5:05 PM Reply   
^^^^^^ All of them?
Old     (dadthedriver)      Join Date: Jul 2004       07-09-2008, 5:50 PM Reply   
Adam "pros dont use the wedge they use ballast" is a pretty broad statement. I personally know pros that do use the wedge.
Old     (ron_mexico)      Join Date: Jul 2007       07-09-2008, 9:29 PM Reply   
chris - based on my experience. the wedge and an load of weight in the front of the boat usually works out allright. that much downforce on the back of the boat creates a significant amount of bow rise. i think the wedge is a brilliant marketing gimmick that functions well up to a decent point. after that. its crap.

too much weight along with the wedge, and the wake begins to wash out do to having a huge foil disturbing the water that is coming off of a clean running surface. the best wake comes from a clean running surface all the way off of the back end of the boat with minimal disturbance.

but what the hell do i know.
Old     (bac)      Join Date: Feb 2008       07-09-2008, 9:40 PM Reply   
Link to Justin's post on the local board here. Pics about halfway down
Old     (texasissippi)      Join Date: Feb 2008       07-10-2008, 9:33 AM Reply   
so i dont know if it was due to us surfing (the boat resting in the water at a different angle)or just a freak accident, but we had not a scratch on the prop or any other under-water parts. it just hit the wedge CLEAN and it sure did make a jolt in the boat i will not soon forget.
Old     (151)      Join Date: Jun 2008       07-10-2008, 4:06 PM Reply   
Thanks for the (few) answers. Now for the real fun!

The reason I asked in the first place is because I am considering replacing the hydrofoil part of the wedge on my vlx with a slightly larger one.

Thinking that more foil surface will create more down force and require less ballast.

Just to save some people the risk of carple tunnell, IF I do this the foil will not be lower in the water than the factory location.

And in hopes that the nay sayers will decide its not worth the long post required to tell me how stupid I am, I am also going to spend this winter repowering my wakesetter with a 6.5 diesel so I can burn 100% biofuel next summer.

And I am thinking about chrome plating my illusion tower.

and, no, well thats all.
Old     (fletch_tx)      Join Date: Aug 2003       07-10-2008, 4:19 PM Reply   
Why not plumb in 750lb sacks into the rear lockers instead? I'm starting to experiment with more weight in the rear instead of running the wedge...I'm starting to think that the drag from the wedge really chews up gas....more than the actual water ballast equivalent would....thoughts anyone?
Old     (westsidarider)      Join Date: Feb 2003       07-10-2008, 4:28 PM Reply   
yea it probably does eat more gas. i like the shape of the wake with the wedge, plus its less water you have to load in or lead you have to carry around all the time. and you can fine tune how much lip it has or doesnt with the power wedge
Old     (waterfreak)      Join Date: Jul 2007       07-10-2008, 4:38 PM Reply   
Take pics of the motor swap and report back on that. Why are you swapping motors? Just to burn bio-diesel or is their something wrong with your current motor?
Old     (fletch_tx)      Join Date: Aug 2003       07-10-2008, 4:49 PM Reply   
Jason...I have to say I've been very pleasantly surprised how bad ass my new 0823lsv's wake is just using stock ballast + 560lbs in pop bags + the wedge. I really thought I was gonna have to load that bad girl down with some lead and water ballast. Everyone that rides with us loves it. I'm soooo stoked over my new baby!
Old     (rallyart)      Join Date: Nov 2006       07-10-2008, 5:38 PM Reply   
Chris, you need to work out the load factor on the bolts that hold it. It already generates 1200# of force at the peak angle and is a pretty effective shape.
If you go larger but with a less efficient design you'll increase the drag load and might still not get more downforce. If you want to play and get more downforce why not just add winglets to the leading fin in the center. This would give you load up front to counteract the extreme load at the stern and lessen your front ballast requirements.
If you're a keen engineer you could work on the trailing edge or tips of the current wedge to increase it's effectiveness.
It's fun to play with ideas. Which reminds me, a small turbine will burn biofuel really well and give you enormous power. Just run a transmission gearbox so you can spool it up faster and have the grunt to get out of the water faster.
Old     (jtnz)      Join Date: Sep 2007       07-10-2008, 5:52 PM Reply   
Jet powered boat? That'd be cool, and you could run it on just about anything that burns, but what do you do about the exhaust?
Old     (rallyart)      Join Date: Nov 2006       07-10-2008, 5:59 PM Reply   
If you directed it up it would add downforce, and be one heck of a towel dryer.
Old     (westsidarider)      Join Date: Feb 2003       07-10-2008, 6:05 PM Reply   
mark- the boat does do very well without the wedge and you dont need to load the crap out of it with weight to get a good wake. but we like to ride with the biggest possible wake. typically we ride with the wedge, stock ballast, including the middle and front tank, about 1100 lbs of lead, and another 700 sack in the middle of the floor in the cockpit area. my other buddy with the same boat, lsv, we run the wedge, stock ballast, a bag across the back floor, a bow sack, and about 700 lbs of lead.
Old     (151)      Join Date: Jun 2008       07-10-2008, 6:18 PM Reply   
Nothing is wrong with the monsoon that came with the boat. I am actually very happy with it.

My wife has an uncle that is big on bio diesel and he has done some interesting things with it.

I got a steal on my boat and the fuel is by far the biggest expense. Plus I just do not like taking money from my friends for gas. At .25$ per gallon the waste oil fuel is unbeatable.

I am really interested in the ideas you mentioned about the winglets for the gorilla fins. But how could they be easily disengaged like the wedge?

I do like the MLS ballast on my malibu it is fast and works very well. Its just the idea of hauling all that weight around all day that I don't like.

Has it been done before, or could we start a thread for wake building without ballast ideas?
Old     (fletch_tx)      Join Date: Aug 2003       07-10-2008, 6:48 PM Reply   
Jason - I'm there with ya man...just saying that I'm pleasantly surprised that I don't HAVE to load it down so much...we've definitely been adding extra weight as we like mackin' wakes too! :-) thanks for "consulting" with me before my purchase!
Old    dabigkahuna            07-15-2008, 3:02 AM Reply   

.25$ per gallon of waste oil fuel??? I don't get it, that doesn't sound right...Please explain how you can get bio-diesel for .25$ per gallon. I hope you can get it for that cheap, but it just doesn't add-up to me.

By the way, what's the diesel conversion going to run you?
Old     (srh00z)      Join Date: Jun 2003       07-15-2008, 7:00 AM Reply   
Waste vegetable oil could be around 10-25 cents per gallon, but biodiesel is around 90 cents to a dollar to produce isn't it? Please document the engine swap and post them up here. Are you using the 6.5L Detroit Diesel that was used in chevy trucks in the 90's before the Duramax came out? Have you found marine exhaust manifolds? I may be mistaken, but I think the motor mounts are the same as a 350 (they were on the 6.2L). I am trying to find a clean, old diesel suburban to run on waste veggie oil. I've always wanted one and my current vehicle doesn't tow the boat well.

(Message edited by srh00z on July 15, 2008)
Old     (xsmini)      Join Date: Dec 2005       07-15-2008, 9:12 AM Reply   
the new manual wedge doesn't even lock down, if it strikes anything, it just flips up.
Old     (hyrific)      Join Date: Sep 2004       07-15-2008, 2:41 PM Reply   
We have an LSV and I never use the damn wedge unless we are surfing. Its eats gas like a son of a bitch. If you have 8 people in the boat with the ballast full it does fine and saves some cash.

If I decided to use the wedge up at 7000 feet elevation we would have to change our prop or the damn thing wouldn't even get up to plane.
Old     (sjmedic)      Join Date: May 2004       07-15-2008, 4:06 PM Reply   
Ok, my .02 also. I run the wedge every now and then, it seems to make a little difference. I prefer (lately) to add ballast instead of using the wedge. It really burns through fuel, and if you are not accustomed to the wake using the wedge, it is shaped a little different. twin 500 in the back and 250 up front, 4-5 people will give you as much wake as you need. No wedge required. BUT, its nice to have if 2 out of the 5 people flake out on 'ya
Old     (151)      Join Date: Jun 2008       07-16-2008, 6:12 AM Reply   
I need to refresh my memory on the diesel specs. Either the 6.2 or the old 6.5 is a very do-able swap for a 350 chevy. I think the 6.2 may be the more reliable engine, but it has been weeks since I started researching.

Isnt waste oil fuel sometimes called biodiesel? I will be using wvo fuel, hopefully next season.

It looks like there are a few if not several companies that make the exhaust and other needed parts for a marinized 6.2 or 6.5

It might not be possible but could a programmer be used to change timming etc. for a more lake friendly power curve?

At this stage (officially the "dude that would be cool" stage) I need to find out how to mate the new engine to the trans, and how to get the perfect pass to work. There are lots of answers I need to get before I will even loosen the first bolt.
Old     (srh00z)      Join Date: Jun 2003       07-16-2008, 6:28 AM Reply   
There is a difference between waste veggie oil and bio diesel. I am unsure of the process on making bio diesel, but it is somewhat involved. As I understand it, it will run in most diesel engines without modifications. Waste veggie oil on the other hand has to be strained. It also has to be heated in order to burn in a diesel. Most kits have tubing in the diesel tank that passes a warming fluid through the tubing. Also, most of these engines have to be warmed up on regular diesel fuel and then you switch to waste veggie oil after the engine is at operating temp.
Old     (trace)      Join Date: Feb 2002       07-16-2008, 6:47 AM Reply   
I stand corrected on justin's boat. Sorry for calling you a troll, and sorry about the trouble with the boat. I hope insurance works out for you.
Old     (trace)      Join Date: Feb 2002       07-16-2008, 6:49 AM Reply   
I looked into making biodiesel a couple years ago. IIRC, it costs around $1 per gal for WVO, about $1500 for the equipment, and 3 hrs labor to make about 30 gal.


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