# Tunnel Hull help



## dearl (Mar 26, 2017)

I posted this on Mean Chicken, thought I'd post it here too with the number of guys running Jets now.

I have a 2010 Lowe Roughneck 1655D tunnel hull powered by a 2008 Mercury 90/65 jet outboard. I recently went through and replaced the floors and decks in .080 aluminum, and used 1.5 x1.5x.125 tubing for braces. Before the mods it had .125 decks and floors which made the boat pretty heavy. Then it would run 32-34 mph with an occasional 36 if the water was flat, and you couldn't make it porpoise. Now with only 2 batteries at the stern, forward console, 19 gallon fuel cell under the front deck, running empty I can only get 33 tops. To say the boat is light is an understatement, The boat drafts very shallow now, which was what I was after, but the lose in speed has me puzzled. New liner, good grating, smooth bottom. Motor runs like a scalded cat.
Before the mods, I could adjust the trim and get In the sweet spot, she would dig with no over spray. Now with minimal trim adjustment I get a lot of spray, then comes the porpoising. It will run with the motor tucked in the tunnel, but at 31 mph. It almost feels like the hull is stuck to the water, I know that some tunnels create low pressure areas causing a vacuum so to speak, and I'm wondering with the new weight distribution, if this is what's happening. I have already planned to move both batteries under the front deck to distribute more weight, the nose of this boat is very light even with the fuel cell under the front deck. 
When I come off of WOT It almost feels like the hull stays "stuck" to the water for a bit and then breaks free and slides fairly easy. From looking at my tunnel and reading some topics here on tunnel dimensions, I'm wondering if some tunnel work would benefit this hull. I have since removed the strake you see inside the tunnel, but haven't had it back In the water yet. I don't have the tunnel dimensions with me but will measure them when I get home and post them later. Here are some shots of the hull when I had it flipped to do some bottom painting, and another of the hull when we took it out after the re-wire and before the rear deck. The boat rides great, has awesome throttle response, goes super shallow, but its not as fast as it was when it was heavier than now, Any thoughts or input is appreciated.


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## dearl (Mar 26, 2017)

I went through and adjusted the reverse gate to make sure it was as tight as possible in the open/forward position, and took some more pictures with the motor at its running height. I've never paid it much attention until now but the tunnel is 6" larger than the shoe on the pump, 3" on each side.

The tunnel measurements are 36" long front to back, 19 1/2" across the front opening, 14" at the rear on the bottom, and 20 1/2" at the rear top. Is it just me or does that seem like a waste of space. Some of you guys know tunnels and I hoping it will be as simple as closing up the tunnel some, that's no problem I can handle that, I just need some direction from someone that knows a lot more about tunnels than I do. Thanks in advance.


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## rotus623 (Mar 27, 2017)

Sounds like the weight balance was perfect and maybe you disturbed it? Are your rpms the same as they were?

I would get a few 80lb bags of concrete and move them around the boat to see if it helps before you actually start moving batteries, etc.


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## dearl (Mar 27, 2017)

rotus623 said:


> Sounds like the weight balance was perfect and maybe you disturbed it? Are your rpms the same as they were?
> 
> I would get a few 80lb bags of concrete and move them around the boat to see if it helps before you actually start moving batteries, etc.



When I purchased the boat originally it was light In the nose like now, and I had the same problem, I moved some things around and installed heavier decks and floors, and it ran well that way, but was heavy and drafted a lot more. Now that its light again, it almost feels like it wants to run there, but with the batteries In the rear, I'm almost certain this changed the dynamics of the tunnel and created a low pressure causing it to pull the stern down more. The spray is ever present with a touch of the trim, something I'm not used too. 

The concrete idea is a good one, but I have 2-30lb. anchors, a 40 lb. bait tank and a 200 lb. man on the front deck and this thing will still bounce your eye teeth out at WOT and I still get spray when I touch the trim. I'm not sure if re-working the tunnel will solve this but everything I know about this boat tells me its more than just the weight distribution.


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## jerseyjimk (Mar 27, 2017)

since you changed some things around the boat,lost some weight.you may have to lower your motor a bit,not by trim but using a different hole.lower or raise the motor. Sometimes 5/16 of an inch makes a world of difference


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## JL8Jeff (Mar 28, 2017)

With my Lowe 1652 jet tunnel and Merc 60/45 I was getting porpoising past 1/2 throttle. I put some extra weight up front and it helped but it didn't go away. I put on the transom wedges and that got rid of it. I have to run trimmed all the way in, if I start to trim up a little, I get spray back. I moved my console forward and put the battery under the console and it seems to run great this way. You tunnel looks a little odd, was it a prop tunnel that somebody modified for a jet? It also looks like your motor needs to be moved down a little, I run with the foot just under the top of the tunnel. I wonder if your pods are grabbing more now if your noes is up because of less weight. You might want to try the wedges to get a little more tucked in.


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## Junojet (Mar 30, 2017)

I'm going to agree as stated above that your motor looks like it is mounted a little high. On my 1756 I have a piece of UHMW between the exit of my tunnel and the bottom of my foot that forces water straight into the jet instead of it going between the jet and transom. Also, my jet has side fins on it to help force water in the jet. I will get some photos of how my jet is setup today or tomorrow. Not sure if doing this would help, but I have been able to run with 4 people a dog and gear over glazed sand bars that have 2 or 3 inches of water covering them. 


Sent from my iPhone using Tapatalk


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## dearl (Mar 30, 2017)

Thanks for all the replies....

I've went back and forth with the idea of welding up the tunnel, and just use it as a mod V/ flat bottom and this is the list of pro's and cons I've come up with so far and how I rate it.

*Tunnel....*

Drafts a little lower at idle. (Con)

Has to have some water to get UP on plane. (Con)

Loose 3-5 maybe more mph on top end. (Con)

Not very fuel efficient. (Con)

Will run in spit (Pro)

*Non Tunnel*

Gain another inch or 2 of static draft (Pro)

Should plane fairly easy from get go. (Pro)

Gain a little top end (Big Pro)

Better fuel economy (Bigger Pro)

Run motor lower on transom (Pro)

I really don't need to run 3" of water on plane, I would rather be able to idle through some tuff spots, Anybody know of any more Pro's and Con's? To weld this Tunnel up I'm gonna have to flip it, It will be tig welded in, no spool gun, I want to make sure its water tight. I did the math on the tunnel and if welded up I would gain another 1.34 cubic ft. of air, almost like another Pod under the boat. That will support another 83 lbs., that along with moving both batteries under the front deck should float this boat level in 4" of water.


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## rotus623 (Mar 30, 2017)

Pros/cons sound about right. Since the tunnel is already there I would just leave it if it were me, but that's me.

I have had plenty of boats, some with tunnel and some without. The tunnel does rob many benefits, but I have run over rock ledges where I would have caused some SERIOUS damage if I didnt have a tunnel. I also have UHMW on my boat, which slows me down even more. Top speed with just me and a light load is 25mph. Me, one other person, and gear loaded up we are looking at 22-23MPH. This is on a 1648 with 60/40 4 stroke. IMO, I don't really want much more speed in the treacherous waters that I run in this rig. That's why I have 2 boats


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## dearl (Mar 30, 2017)

rotus623 said:


> Pros/cons sound about right. Since the tunnel is already there I would just leave it if it were me, but that's me.
> 
> I have had plenty of boats, some with tunnel and some without. The tunnel does rob many benefits, but I have run over rock ledges where I would have caused some SERIOUS damage if I didnt have a tunnel. I also have UHMW on my boat, which slows me down even more. Top speed with just me and a light load is 25mph. Me, one other person, and gear loaded up we are looking at 22-23MPH. This is on a 1648 with 60/40 4 stroke. IMO, I don't really want much more speed in the treacherous waters that I run in this rig. That's why I have 2 boats



O.k. the numbers you posted for your boat carrying that weight brings me to my point, I'm only running 8 mph faster than you with a lighter boat and a 90/65 2 stroke. Motors not the problem, the power is there, Its almost like I cant get the hull to respond without trying to jump out the water. I can go from a dead stop to 33 in a few seconds, no problem, but when I try to trim it ( and I have always had to at WOT to get to the sweet spot) its like you throw an anchor out, I know its drag but why, the stern is lighter than its ever been. I'll tell you why, the a$$ is getting pulled down lower In the water, how, no clue but I do know before when it was heavy something made the hull "break" free but now its almost like the hull is to light to get away from it. I do know its got something to do with the tunnel.

I'm not convinced I'm welding it up yet, I'm going to try the things MT told me before I decide anything. If it will respond after the extension mods then I'll keep it. If not its got to go.


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## rotus623 (Mar 30, 2017)

Running 8mph more with a 90/65 is probably about right, when comparing apples to apples. I wouldn't expect to get too much more out of it. I had a prop 75hp on a 16' aluminum boat and it would max out at 36mph with a light load, trimmed out. Just food for thought here.


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## Ebug (Mar 30, 2017)

You might take a look at venting your tunnel to release some of the suction it seems to be creating with the current attitude of the hull.

Try a google search for "Vented Tunnel Hull"

You will see what others have done. A creative person could rig up a temporary/test system using Ø1/2 PVC and a ball valve hanging over the transom turning under/into the tunnel with a 180 pointing the outlet towards the stern. Try to get that 180 outlet as far forward in the tunnel as you can and not have it stick out. The ball valve gets adjusted while under way to allow small amounts of air to enter the front of the tunnel to disrupt the suction. 

The folks I know with flats boats with vented tunnels get them adjusted the way they want and never adjust it again.

Just a thought.

Rob


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## stinkfoot (Mar 30, 2017)

What did you paint it with and did it run fast after painting or are the drop in speed and the painting at the same time?


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## gabeskillzz05 (Mar 30, 2017)

Dearl,
I have a Lowe 1752D with factory tunnel and have the same issues that you describe. I only have a 50/35 at the moment. The stern feels like it is sucked down, if I'm on the lake at WOT and I run over a wake sometimes the boat will break free...the bow will sit down and I will pick up 2-3mph instantly. You can feel the speed increase and I have gps on my garmin that verifies it. 

I tried moving the motor up/down, all trim angles and transom wedges to no avail. I really think it has to do with the tunnel extension angle. On my boat the tunnel goes from 0 to 2.5" and is the same angle from start to finish. Looks the same as yours. I believe the section of the tunnel that extends past the transom should be parallel to the bottom of the hull. The way it is now, it is trying to pull the water up and in return sucking the stern down. 

I'm currently rebuilding a 90/65 and waiting to put that motor on before I cut into that tunnel extension and bend it down to be parallel with hull. If you look at the top end tunnel manf this is how the extensions are setup. That's my .02


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## gabeskillzz05 (Mar 30, 2017)

I also coated my hull with wetlander over the summer hoping it would help and didn't make a difference. Pic for reference, level is on the bottom of hull.


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## dearl (Apr 2, 2017)

rotus623 said:


> Running 8mph more with a 90/65 is probably about right, when comparing apples to apples. I wouldn't expect to get too much more out of it. I had a prop 75hp on a 16' aluminum boat and it would max out at 36mph with a light load, trimmed out. Just food for thought here.



I dont buy it, 33 is not about right, like I said earlier I have had this boat up to 36 when it was 200 lbs. heavier.



Ebug said:


> You might take a look at venting your tunnel to release some of the suction it seems to be creating with the current attitude of the hull.
> 
> Try a google search for "Vented Tunnel Hull"
> 
> ...



From what i've read you can only vent a prop tunnel, when you open the vent it pulls air inside the tunnel to break the low pressure area, this allows air to enter the tunnel and would probably end up cavitating the pump.



gabeskillzz05 said:


> Dearl,
> I have a Lowe 1752D with factory tunnel and have the same issues that you describe. I only have a 50/35 at the moment. The stern feels like it is sucked down, if I'm on the lake at WOT and I run over a wake sometimes the boat will break free...the bow will sit down and I will pick up 2-3mph instantly. You can feel the speed increase and I have gps on my garmin that verifies it.
> 
> I tried moving the motor up/down, all trim angles and transom wedges to no avail. I really think it has to do with the tunnel extension angle. On my boat the tunnel goes from 0 to 2.5" and is the same angle from start to finish. Looks the same as yours. I believe the section of the tunnel that extends past the transom should be parallel to the bottom of the hull. The way it is now, it is trying to pull the water up and in return sucking the stern down.
> ...



Sounds like we've got the same problem, i agree with you on the tunnel textension being parellel to the hull, A guy on another forum gave me the same recommendation on how to set it up. After weighing all my options, I still think Im going to close it in. I like the idea of doing away with that issue all together, plus the Pro's out weigh the cons hands down.

I took the boat out yesterday morning, lake was slick as glass, new liner, impellor adjusted perfect, WOT was 33.1 and it started to porpoise bad, I noticed the water coming out of the tunnel was directed to the bottom of the pump housing with the jack plate all the way up, Im sure adjusting the tunnel extension would fix this, but my plan is to move the 2 stern mounted batteries forward under the front deck, and weld the tunnel up to create a true MV/Flat bottom hull. This will give me 3 things, more fuel economy, more top end, and more draft at idle. It will take me a couple of weeks to get this done, i got a couple of boats to finish up then I can get back on mine.


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## redrum (Apr 2, 2017)

What happens when you smack that PTT motor? Does your PTT have a way to disengage so it can pop up out of the water? No? That's a PRO of having a tunnel on boats over 60/40. Tunnels can bite in a turn and act like a skeg.

If you want to go faster move all your stuff to the back. Fuel in rear makes most sense since the engine is back there and it keeps unballasted weight in the stern which can hold the load better instead of being up out of the water.


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## dearl (Apr 2, 2017)

redrum said:


> What happens when you smack that PTT motor? Does your PTT have a way to disengage so it can pop up out of the water? No? That's a PRO of having a tunnel on boats over 60/40. Tunnels can bite in a turn and act like a skeg.
> 
> If you want to go faster move all your stuff to the back. Fuel in rear makes most sense since the engine is back there and it keeps unballasted weight in the stern which can hold the load better instead of being up out of the water.



Really? Wow....Move all the weight to the rear of the boat to speed up and stop porpoising.....Ok.

Anyway, not intersted in fastER, but i do want this boat at or above the speed it was running before the weight was reduced at least 200 lbs, and get rid of the porpoising.


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## CedarRiverScooter (Apr 2, 2017)

If you do weld up the tunnel, maybe make it a sealed chamber & at least get some flotation benefit out of it.


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## redrum (Apr 2, 2017)

I'm guessing you wanted a more complicated answer. Looks like you put a ton of work into your boat to drop a few pounds. I'm guessing to go faster and now it has your weight distribution jacked up. It looks like your motor is too high, maybe not. You need to be trimmed out so the jet nozzle is flat and pushing your boat forward not UP.


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## dearl (Apr 3, 2017)

redrum said:


> I'm guessing you wanted a more complicated answer. Looks like you put a ton of work into your boat to drop a few pounds. I'm guessing to go faster and now it has your weight distribution jacked up. It looks like your motor is too high, maybe not. You need to be trimmed out so the jet nozzle is flat and pushing your boat forward not UP.



A few pounds is an understatement. All of the mods that were done were to shed weight, i need a hull that is light and drafts very little, Before the mods the boat was very nose heavy, took forever to get on plane, did not porpoise and had no spray coming over the transom and would run 33-36 mph with ease and drafted 6 - 8" of water. I could trim the motor to get it up to speed and she would tote the mail with no spray.

Now the hull is very, very light, sits on top of the water drafts maybe 4" jumps on plane and will hold it down to 14 mph top speed is 33 and porpoises very bad at that speed. The spray is unreal if you even think of touching the trim.

It is not hard to for me to beleive that with at least a 200 - 300 lb weight reduction that the boat would be faster than it was before,

I know now that the tunnel extension is the main culprit, its causing drag on the engine, plus the angle of the foot is catching the water coming out of the tunnel at a weird angle causing the spray. I have removed the existing transom extension, and plan to build a new one parellel to the hull with a adjustable spray rail, this should allow me to lower the engine on the jack plate, and adjust on the fly to get where it likes to run.


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## handyandy (Apr 3, 2017)

Before you go through all the trouble of welding up the tunnel I'd keep messing around with motor height/weight distribution before you go through all that work. I can understand wanting to get rid of a tunnel, to me, and to you as well the cons of a tunnel outweigh the pro's. This is more so on flat bottoms it seems like. Wooldridge and few other of the northwestern boat builders seem to have the tunnels for outboard jets down pretty well, but their boats with them aren't a flat bottom like yours and are specifically designed for a tunnel. With that said if it were me I'd mess around with weight distribution more before I went through all the work of welding up the tunnel. The bags of cement or some other heavy weight that's easy to move around works well for experimenting before you actually move something like the batteries. I suspect you need more weight up front being you use to have heavy flooring throughout the boat that is gone now that helped weigh the front down apparently just right since you got 36 out of it before.


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## dearl (Apr 3, 2017)

handyandy said:


> Before you go through all the trouble of welding up the tunnel I'd keep messing around with motor height/weight distribution before you go through all that work. I can understand wanting to get rid of a tunnel, to me, and to you as well the cons of a tunnel outweigh the pro's. This is more so on flat bottoms it seems like. Wooldridge and few other of the northwestern boat builders seem to have the tunnels for outboard jets down pretty well, but their boats with them aren't a flat bottom like yours and are specifically designed for a tunnel. With that said if it were me I'd mess around with weight distribution more before I went through all the work of welding up the tunnel. The bags of cement or some other heavy weight that's easy to move around works well for experimenting before you actually move something like the batteries. I suspect you need more weight up front being you use to have heavy flooring throughout the boat that is gone now that helped weigh the front down apparently just right since you got 36 out of it before.



I agree, Wooldrige has their tunnel boats figured out, and with that application it works great I'm In the process of designing a new tunnel extension, plus I'm going to move the batteries anyway, that's 100 lbs. I don't need on the stern. I was thinking when I did the mods that it would be too much weight on the nose, now that I have driven the boat, I know it can handle it and more. I don't want to much up there but I really think it may be enough to help keep the nose down once I get the drag issue fixed. I know some guys are thinking that's a lot of weight on the front, but believe me when I say the nose of this boat is super light.

Before the mods, I had 2 batteries, onboard charger, and a 40 gallon live well under the front deck, all construction was with .125 plate and with me @ 215lbs. that was a lot of weight. and it would still run like a scalded cat.

Now the nose, as lite as it is with only a 19 gallon fuel tank, and me, my son, and everything else In the boat on the front deck, it wants to stand straight up In the air @ 33mph.

Some pics of the destruction process, I got to clean the old welds off, doesn't help I built the old extension out of 3/16 aluminum plate.


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## dearl (Apr 5, 2017)

Got the old welds cleaned off, mocked up the new tunnel extension angle with a piece of angle iron, set the shoe were it needs to be with the jack plate, looks like I should be able to drop the motor down a couple bolt holes on the motor. I'd like to have it set at full extension, the shoe is were it needs to be with no risk of placing the shoe on top of the extension. By the tape the extension needs to be 9.5 -10" long? I plan to use UHMW stock to make the top of the extension adjustable. Also I'd like to extend the extension from the bottom of the 45 degree drop all the way under the pods to the sides of the boat, trim tab so to speak. Any thoughts?


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## handyandy (Apr 5, 2017)

I'd just make the extension first see how it does before making the trim tab type things. Keep the changes one at a time now to see what effects what.


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## dearl (Apr 11, 2017)

Got the new extension welded on this weekend, after all was said and done, it ended up being 9.5' long and parallel to the hull. I cleaned every thing up last night and took a lot of pictures from different angles so you can see what's going on. I still have to add the UHMW stock to the top and bolt it down for the adjustable plate, and raise the motor up to the last bolt hole. This should put the front roll pin even with the plate with the jack plate all the way up and motor tucked in. Let me know what you guys think.


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## redrum (Apr 11, 2017)

Interesting looking tunnel. I've never seen one extended like that to compensate for a jack plate. It's like the spray plate and tunnel are combined. I'm interested to see how it works. It seems like that semi-circle cut would create an awkward vortex with the water feeding the pump.


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## gabeskillzz05 (Apr 11, 2017)

Eager to hear how this works. Once you get it dialed in I'll bring my boat down so you can do it to mine!!! :lol:


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## dearl (Apr 12, 2017)

I spent yesterday afternoon moving the motor up to the last bolt hole, and making the adjustable tab for the tunnel extension. It looks perfect, height is good (I HOPE)! I used a piece of .080 aluminum for the tab for now, cant find 1/4" uhmw around here so I'll order a piece and replace the aluminum later. I know if the shoe touches the aluminum all I'll hear is a rattle. Plan to take her out today for a test run, I'll post results for you guys tomorrow.


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## dearl (Apr 14, 2017)

Took the boat out yesterday, I like the way the boat feels with the new plate. I have more control of the throttle now, the spray is gone completely, but It still wants to porpoise at WOT. I know now that I need to distribute the battery weight to the front. I did pick up some speed, top speed was 34.4 but I had to let her bounce a little to get up to that. She's got a few mph left in her, once I can play with the trim without the porpoise I believe she'll be perfect.


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## mphelle (Apr 14, 2017)

In my opinion, the floatation pods are mounted incorrectly, causing the porpoising. I would remove them and move the batteries to the front compartment. I would also lengthen your prototype flap since I think you will find yourself trimming up more.


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## dearl (Apr 17, 2017)

mphelle said:


> In my opinion, the floatation pods are mounted incorrectly, causing the porpoising. I would remove them and move the batteries to the front compartment. I would also lengthen your prototype flap since I think you will find yourself trimming up more.




Not understanding what is incorrect about the way the pods are mounted.

Started the big battery move this weekend, gutted the front end to install 2 new battery mount pads, got those welded in yesterday. Batteries are re-mounted, just about done with the re-wire, will begin installing the front deck and hooking everything back up. should be ready for a water test by Thursday. If nothing else it will draft less on the stern now, 2 batteries and an onboard charger are pretty heavy.


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## mphelle (Apr 17, 2017)

Battery project looks good, you have a lot more energy than I do. Your pods were mounted high by someone who thinks keeping them out of the water while on plane will reduce drag. In your case when you try to raise the bow with trim, the pods tip down catching the water and forcing the bow back down, and so on.




Others, including Beavertail, think the bottom front on the pod should be flush and smooth with the bottom and angled up about a half inch in the rear to allow some trim. Ranchero50 had similar issues with his pods and used an interesting solution to porpoising. https://www.tinboats.net/forum/viewtopic.php?f=83&t=8385&start=240 about halfway down the page

Your pods have the wrong angle to just move them down, which is why I suggested removing them to test the porpoising theory.


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## redrum (Apr 17, 2017)

Nice work. Do you have hatches on the deck to access the batteries? Is that area in the center for your fuel tank? Are those your TM batts? Do you still have a start battery in the back? Hope it works out for you it's frustrating putting a ton of work into something and it not working out.


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## dearl (Apr 18, 2017)

Well I got a lot done last night, pretty much buttoned everything back up, still have the fuel fill to install and the front deck hatch. I plan to bleed the steering today while my son is there, that process takes 2 people, other than that, should be ready for a water test Wednesday.




















mphelle said:


> Battery project looks good, you have a lot more energy than I do. Your pods were mounted high by someone who thinks keeping them out of the water while on plane will reduce drag. In your case when you try to raise the bow with trim, the pods tip down catching the water and forcing the bow back down, and so on.
> 
> View attachment 5
> 
> ...



And this makes sense....Once I get it back on the water and test it out, if I still have the degree of porpoising as before, I will play with the pods. I can drop them down if need be, probably have to customize the pods but it can be done.


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## dearl (Apr 18, 2017)

redrum said:


> Nice work. Do you have hatches on the deck to access the batteries? Is that area in the center for your fuel tank? Are those your TM batts? Do you still have a start battery in the back? Hope it works out for you it's frustrating putting a ton of work into something and it not working out.



Nothing in the back now, everything is under the front deck. I plan to order 2 new hatch's for the front bulk head to access both batteries.


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## mphelle (Apr 18, 2017)

Crazy fast progress, if you used a video camera it would be better than most cable shows. If you have a GoPro or another waterproof option, hang it off the back during your test.


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## dearl (Apr 19, 2017)

Got everything back together yesterday, bleed the steering, and took it out for a test run. Wow! moving the batteries made a huge difference. No more spray, better draft at idle and porpoising is all but gone. I mean I can still make it porpoise if I trim it to the moon but it ran incredibly well. Boat jumps out of the water, planes very easy and hit 33.7 and would hold there without jumping. I could probably get it a little faster if I would have played with it more. I do believe the pods are holding me back from hitting 35, but if I remove them I'll lose my draft at idle and I'm not willing to do that. I got a couple of videos I'll try and get posted later.


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## rotus623 (Apr 20, 2017)

dearl said:


> rotus623 said:
> 
> 
> > Running 8mph more with a 90/65 is probably about right, when comparing apples to apples. I wouldn't expect to get too much more out of it. I had a prop 75hp on a 16' aluminum boat and it would max out at 36mph with a light load, trimmed out. Just food for thought here.
> ...



Just sayin.......

Either way, boat looks great. I love the console on the casting deck and would love to see some side shots!


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## handyandy (Apr 20, 2017)

75hp on a 16ft aluminum and only 36 that's not very good something wasn't right either set up or prop. Friend has a 3/16 thick 2060 with a 1979 70hp johnson we get 36-37 out of it when it's just us and fishing gear in it. It goes down once it has the big duck blind on it, decoys in it, and couple more guys hunting.


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## rotus623 (Apr 21, 2017)

handyandy said:


> 75hp on a 16ft aluminum and only 36 that's not very good something wasn't right either set up or prop. Friend has a 3/16 thick 2060 with a 1979 70hp johnson we get 36-37 out of it when it's just us and fishing gear in it. It goes down once it has the big duck blind on it, decoys in it, and couple more guys hunting.



Nah man it was set up perfectly. Motor was cherry and tached out at 5800rpms. It was a V hull starcraft that had plenty of power. It had a decent deadrise so Im sure that hurt the top #'s some.


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## handyandy (Apr 24, 2017)

v hull makes since was thinking it was a typical mod v nearly flat bottom or flat bottom boat.


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## dearl (Apr 24, 2017)

rotus623 said:


> dearl said:
> 
> 
> > rotus623 said:
> ...



Well, we took the boat out fishing Friday morning, loaded down with all the gear we hit 33.1 WOT. moved the bait tank around a little, played with the anchor position some and hit 34.5 on slick water. That's with 2 - 200 lb. men, 2 - 30 lb. anchors, a 30 gallon bait tank full of water, and numerous rods and tackle. Also found a couple of walnut hulls wedged in the discharge spout of the pump. Not sure how long they had been In there, but could tell a noticeable difference once those were removed. Boat rides really good, I'm happy with it, I may play with it some more later but right now I'm going fishing.


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## rotus623 (Apr 24, 2017)

dearl said:


> Well, we took the boat out fishing Friday morning, loaded down with all the gear we hit 33.1 WOT. moved the bait tank around a little, played with the anchor position some and hit 34.5 on slick water. That's with 2 - 200 lb. men, 2 - 30 lb. anchors, a 30 gallon bait tank full of water, and numerous rods and tackle. Also found a couple of walnut hulls wedged in the discharge spout of the pump. Not sure how long they had been In there, but could tell a noticeable difference once those were removed. Boat rides really good, I'm happy with it, I may play with it some more later but right now I'm going fishing.



Sweet!!! You did one hell of a job on that boat man!


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## gabeskillzz05 (Apr 26, 2017)

What grade aluminum and thickness did you use for the tunnel extension?

Are you using a mig setup? If so what type of wire and diameter do you recommend for the things you have done on the boat?


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## dearl (May 1, 2017)

.125 aluminum plate using a spool gun with ER4043 wire in 3/64"


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## dearl (May 6, 2017)

We have had the boat out several times so far, played with weight distribution even more, took the pump apart and found a couple of pieces of junk in the nozzle, I had it shimmed to .030 so I re-shimmed the impellor to .015 while I had it apart, guess what I found.....the other 1.5 mph Lol. WOT speed is now 35.6 on a glass lake, 35 on a ripple. THIS THING WOKE UP BIG TIME! Planes in 2 boat lengths, jumps out of the water, and holds plane down to 14 mph. I'm happy with it, this is the boat I was used too, I still have to paint the floor and install the new front bulkhead battery hatch's when they arrive but she's done, and I'm glad. Now I can move on to my V-Hull.


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