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Thread: DF Vortex 34 Hydro Build

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    Default DF Vortex 34 Hydro Build

    Hi All,

    New to OSE, but been in boats a long time. This is my first FE build, I ran 0.40ci nitro motors in a 36" plywoodhydro hull some years back. I have some stuff stuck over on another thread, I'll copy/paste over to this. The forum scene is new to me, so just let me know if I can use it better. I have a thick skin, and love to have fun. I take this hobby seriously, but seriously folks, what's to be real serious about? It's all good! I spent close to 40 hours reading posts and learning, before even stepping out to post! Really good stuff on this forum!

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    ProperChopper and I started chatting about this hull. Here's what I had on the other thread:

    What prop did you end up with? I'm putting an 8S, Leonard 40X72 1050kV to start, then I have a 1250 40X82 motor to kick it a little harder. It's been a while for me, but I'm really looking forward to going electric, gas powered boats were a PITA! I was wondering if you could share what prop you are currently working with. I have Grim Race 38X55, 2 blade High Lift to start out with. I have a Grim Racer 40X57, 3-blade high rake prop to step it up. Is a 42X63 prop about it for this hull?

    I'll get some picks on the sponson mods I'm going to be doing. The room in this hull is awesome, love that! I plan on putting the length of the four 5200, 2s batteries across sideways, just starting at the top of the hatch. They go out across the drop off for the sponsons. Thinking of mounting a floorboard for the batteries in there. I want the CG weight components split out, getting weight well forward and placing the front of the motor 13-7/8" from the back of the transom. That still leaves ample room for the ESC and Cap Board in between the motor and the battery pack. I think about CG like a teeter-totter. The longer the arms are from the fulcrum, the slower they move. When the arms get short, then the speed of the teeter-totter goes up dramatically, which represents the boat porpoising, which is not the play. I'm setting my rudder to the left like your model. That seems to make the most sense for a right turning boat running a CCW prop. Prop torque will try to pick up the left side, so setting the rudder left helps stake that side down.

    Another trick I was going to employ was to shim the left side sponson up about 1/8" from the right. This really helped in GP boats for turning. My brother is still running in GPW, has a 28', 500CI blown on alcohol motor. (Check out YouTube, search for GP55) I know the dynamics don't entirely scale, but weight shift and corner planting should involve the same physics.

    Sorry to load you up this way, I just loved the way your hull turned out and value your building skills and experience tremendously. One more point to ask you, strut angle. I'm looking at 17 degrees, going into a single 10" radius bend to the strut. There is something I want to try... I found that the stainless steel tubing on OSE was a perfect fit for the 0.187" flex cable without a liner. It has about 0.004 - 0.005" per side clearance, perfect for grease. The stainless has a thicker wall than the copper tubing normally used. Also, I find the "stickiness" of stainless to be far less that copper, something that is termed "stiction", so I believe it will not have a tendency to grab the cable. You think it's worth the try?

    Well, ProperChopper, getting long here. I hope that we can meet up some time, I have enjoyed getting to know you some on the forum. I promise to get pics out on the build. You know I just hate stopping work to take pictures, but they can be very valuable and may help others enjoy this great sport!

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    I made up an AutoCAD drawing showing a Side View of the drive line angle I want to use on this boat. Having it in AutoCAD let's me really explore options. This drawing will grow as the build progresses.
    Attached Files Attached Files

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    I'm making this an 8S system. I know many of the viewers will say that's too much, but what I'm trying to accomplish is to make delivered power more with voltage and bring the current down. The secret here, in my opinion, is to select a motor that has a higher impedance than motors rated to run at lower voltages. Impedance is not resistance. It is the dynamic resistance the motor puts up under load conditions, and has much to do with both initial coil resistance and the initial coil inductance. The coil resistance is what many people see on the motor sites when they show motor specs. It has NOTHING to do with the actual impedance while running, unless the prop stops completely while still getting a load speed signal.

    So, I have a Leonard 4074 1050kV motor, rated to 45V. The Leonard web site clearly shows the initial resistance higher, indicating it has more windings in it. So initial inductance is higher as well. So the key to me to making this work, it to NOT BE STUPID and put a bunch of prop, or motor load on this. I have a Seaking 130 HV, but really wished I had a Swordfish data logging unit instead. That's the only way to go! If I do this right, then I should get increase run time by dropping the current that is required of the batteries. It's better on the batteries and the whole electrical system in general. I'm using four, 5200mAH in series running to the stated motor and ESC. I do have a Leonard 4082 1250kV motor to put in there once I learn about prop capabilities on this hull.

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    Default Shot of the component placement

    Here's a pic of the planned component placing. I can move the batteries +/-1" from there, should give me good CG tuning range... The motor is where the CAD drawing I posted earlier indicates it needs to be to get a 17 degree stuffing box.
    Attached Images Attached Images

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    Quote Originally Posted by CraigP View Post
    ProperChopper and I started chatting about this hull. Here's what I had on the other thread:

    What prop did you end up with? I'm putting an 8S, Leonard 40X72 1050kV to start, then I have a 1250 40X82 motor to kick it a little harder. It's been a while for me, but I'm really looking forward to going electric, gas powered boats were a PITA! I was wondering if you could share what prop you are currently working with. I have Grim Race 38X55, 2 blade High Lift to start out with. I have a Grim Racer 40X57, 3-blade high rake prop to step it up. Is a 42X63 prop about it for this hull?

    I'll get some picks on the sponson mods I'm going to be doing. The room in this hull is awesome, love that! I plan on putting the length of the four 5200, 2s batteries across sideways, just starting at the top of the hatch. They go out across the drop off for the sponsons. Thinking of mounting a floorboard for the batteries in there. I want the CG weight components split out, getting weight well forward and placing the front of the motor 13-7/8" from the back of the transom. That still leaves ample room for the ESC and Cap Board in between the motor and the battery pack. I think about CG like a teeter-totter. The longer the arms are from the fulcrum, the slower they move. When the arms get short, then the speed of the teeter-totter goes up dramatically, which represents the boat porpoising, which is not the play. I'm setting my rudder to the left like your model. That seems to make the most sense for a right turning boat running a CCW prop. Prop torque will try to pick up the left side, so setting the rudder left helps stake that side down.

    Another trick I was going to employ was to shim the left side sponson up about 1/8" from the right. This really helped in GP boats for turning. My brother is still running in GPW, has a 28', 500CI blown on alcohol motor. (Check out YouTube, search for GP55) I know the dynamics don't entirely scale, but weight shift and corner planting should involve the same physics.

    Sorry to load you up this way, I just loved the way your hull turned out and value your building skills and experience tremendously. One more point to ask you, strut angle. I'm looking at 17 degrees, going into a single 10" radius bend to the strut. There is something I want to try... I found that the stainless steel tubing on OSE was a perfect fit for the 0.187" flex cable without a liner. It has about 0.004 - 0.005" per side clearance, perfect for grease. The stainless has a thicker wall than the copper tubing normally used. Also, I find the "stickiness" of stainless to be far less that copper, something that is termed "stiction", so I believe it will not have a tendency to grab the cable. You think it's worth the try?

    Well, ProperChopper, getting long here. I hope that we can meet up some time, I have enjoyed getting to know you some on the forum. I promise to get pics out on the build. You know I just hate stopping work to take pictures, but they can be very valuable and may help others enjoy this great sport!
    I'm still testing props. I've used a 452/2 and a 450/3 - both Octura's. [One thing is that with the TP Power 4070, which is actually 40mm X 100mm, I could spin anything with all that (silly/unnecessary) horsepower.]

    Your 8S 1050KV setup may want (at somewhere near 34K rpm) a larger diameter prop - your 4072 should be able to handle larger wheels - depends how fast ( and how long) you want to run. We're in somewhat uncharted territory with this hull - AND both Jay and Howard's V34 are (like me) rigged for 4S2P "P" Class racing so our props may not be the ones you'll do best with.

    The stainless stuffing tube makes sense - theoretically less coefficient of kinetic friction 'tho in my case I've got enough HP that it won't matter much. One thing ; in your diagram your stuffing tube resembles two straight sections with a bend in the middle. Better to have more of a continuous gentle "curved" shape.

    You are correct about prop torque and its effect on the LF sponson lifting. I 've added weight in the LF tip to minimize this.
    2008 NAMBA P-Mono & P-Offshore Nat'l 2-Lap Record Holder; '15 P-Cat, P-Ltd Cat 2-Lap
    2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
    '11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono

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    That's a 10" bend radius in there now, I'm going to try some bigger ones and see what it looks like. Trying to shoot for a 1.25" strut centerline depth, I think the sponson work should help make that happen. Not easy changing the strut depth once the boat is complete! I'm thinking to start at running the prop at a neutral angle, it may need running the prop down about 1.5 degree.

    Yeah, my wheels are small! I have some nephews and nieces that would like to learn how to drive, so I thought they would be good learning props, for them and me! It was ALOT of work thinning and polishing those wheels, my freaking fingers hurt... Now they got that nice little "ring" to them when you wipe your finger across the edge. I'll cup them a bit after working out the CG and basics.

    Actually shooting for about 26KRPM's on the 1050 motor with the prop staying hooked up. I may have to run the switching frequency at 12Khz to limit the power to the motor.

    Appreciate your feedback...

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    Default New CAD Print, 15" Radius on Stuffing Box

    Here's 15" and you're right ProperCHopper, it does look more gentle. I'll have to get a big piece of tubing, that radius ends about 3/16" from entering the strut. I'll have to bend it, then cut it back...
    Attached Files Attached Files

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    Default Sponson Pics

    Hi All,

    I've been working on my DF vortex 34 Hydro build. Going slow, been hammered at work! What's that all about? Doesn't my boss know my htydro build is more important? LOL!

    I have some sponson rework pics to share with you. As posted earlier, the stock sponsons are not what I want. They have way too much lift angle, too much side angle and they "swoop up" towards to front, which makes them sticky in rough water. A long time ago, I ran sponsons like the pics and found that the boat was much more stable all around. That was on nitro, hoping the FE boat does the same.

    The wooden rails put down as a base frame are made of laminating 5 pieces of 0.25"X0.25" basswood rails together with marine epoxy. They are incredibly light! I then put in fiberglass and resin inside the channels to re-enforce the epoxy bond. The actual "skin" of the sponsons is T6061-T6 aluminum plating, 0.031" thick. They are held by 4-40 brass wood screws. This thin aluminum I found holds up much better than wood, that eventually starts to show the rails through it after a couple of seasons of pounding on it.

    The site won't take all the pics, so I'll put them on in separate posts.

    Race on All!
    Attached Images Attached Images

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    Default SPonson Pics #2

    Second set of sponson pics.....
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    Default Sponson Pics #3

    Third set of sponson pics....
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    looks nice and neat but i wouldn,t like to race against this Iron Maiden , lol.

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    It does have a battle ready look! All the materials added 0.74lbs to the boat. The sponson design was originally created by Ron Jones. It flattens out the angles, allowing the boat to "skip" across rougher water, like a skipping stone. When the boat hits a crest, it pops up a bit. That produces negative strut angle that brings the boat back down. The rails deepens the sponsons, which opens the air bleeds behind the sponsons. This controls the air under the boat more effectively than air dams. Air dams work to a point. Once beyond that, the boat will snap-flip because the dam itself creates additional trapped air.

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    Interesting sponson work. My 24 vortex runs great in a little chop. Maybe the larger hull rides differently.

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    I was referring to ugly race water. The other goal is WOT turns, in race water. Others on this site and other sites wouldn't put the 34 Vortex in its stock configuration into the stable category. They like to sponson walk and they run light on the front. Stock, they do trap too much air, resulting in quick executing blow overs. They also like to hook in corners when hitting side swells. This boat will skip, never getting to that sponsons never touching ride. Some say slower, I say you have to finish to win! You can't win when the boat is upside down... definitely not a SAW configuration!

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    Here's a short clip of my DF Vortex 34 running last weekend. I lowered the strut after this clip and adjusted the turn fin. It ran much more settled than this clip. But it's looking pretty good here. It has a small motor in it now, until I get comfortable driving it. The motor is a Leopard 4074 1050kv running 8s with a SW 150a Pro+ ESC. It has a Prather S220 prop on it in this clip. It's now running a M545. GPS logged this run at 52mph, probably on the straights. I'm bogging the near corner badly, but it feels tight coming at me.

    https://youtu.be/_lUkHAYp-aI

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    Craig,

    Looking good Appears that the sponson mods were worth the effort. Now the next step is to put some more power to it ; The 4082 - size Leo [or the TP Power 4060] will give more top end and test the handling in what likely will be the high 50 mph's or (propped up) the 60 mph's. For reference ('tho not apples to apples) my P-Cat Cheetah (running extra loose) with the TP Power 4060 {2040KV/4S2P} routinely/comfortably spins a 450/3 and has (for 2-lap time trials) a 452/2.

    Here's a completely embarrasing initial run with a 450/3 prior to adding an air dam and lowering the strut (the tail fins are to aid lateral stability at speeds over 200mph ). Attempts at full throttle were simultaneously accompanied by a nice lakeside lunch while awaiting the boat's re-entry into the Earth's atmosphere :
    https://www.youtube.com/watch?v=0Cdexf5jz3whttps://

    Subsequently added air dam, lowered strut, added ballast in LF sponson tip, chickened out & throttled back to approx 1/3 throttle . Boat ran much smoother but the slower test speed really didn't indicate what would happen when spooled up but water & wind wasn't in my favor + after race guys wanted to pack up & close lake: [ speed clocked with calendar]

    https://www.youtube.com/watch?v=qKEH2yqruDA

    Now that the racing season is basically over at Legg (and the warm weather weed problem is starting to clear up ) I'll spend some more time mostly prop testing. I over-motored this build to see what the TP Power 4070 2200 KV 100mm can motor was capable of. It can likely power my Ford Explorer
    Last edited by properchopper; 09-27-2017 at 03:00 PM.
    2008 NAMBA P-Mono & P-Offshore Nat'l 2-Lap Record Holder; '15 P-Cat, P-Ltd Cat 2-Lap
    2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
    '11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono

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    Thanks Tony, it's been a lot of work but really a lot of fun to drive! The boat shows no signs of getting "Flippy". No hooking characteristics either. As you mentioned, it time to put the proper power to it. I have a 4082 1250kv to start turning larger props. The little motor is getting about maxed out with a M545. I have a M645 to try on it when I do the motor swap. The big delay is and has been, my inability to drive the boat! Before, at 50mph, the boat was always ahead of my concentration. I'm just getting into the 60's and have to learn that level. It takes a lot of thought, I really respect the talent of the good race drivers, it's not a trivial skill!

    The next step is to try a 4s setup, to see about a P Sport setup. I have some batteries to make a 4s2p, 10,000mah battery pack, it just fits. I'm getting another pack that's 4s2p, 8,000mah, a bit lighter. I have a TP 4050 2310kv motor to couple to the 4s pack. I'm currently running a SW 150A Pro+ ESC on the 8s pack, highest current has been about 90A. That's a real sweet combination! The little motor only runs about 70A, the larger 4082 ran the higher current. I have a SW 220A Pro ESC to run the 4s pack.

    I ran on Tuesday and found the steering too sensitive, so I cut down the rudder some. It's a dual water port, 1/8 scale rudder (Speedmaster) and have been slowly widdling it down to proper size. It got sensitive when the speed picked up with the M545... You know, working the setup out is the real kick for me!

    The sponsons are pretty radical, most wouldn't think the numbers would work, but they do! The left sponson is 1/8" lower than the right. The angle on the right is 2.5 degrees and it's 1.3 degrees on the left. This forms a solid outside runner, allows the right sponson to run with less drag. The right sponson is 0.20" deeper than stock. This opens the air trap up behind the sponsons, spilling the air this hull likes to accumulate stock.

    There is also a very aerodynamic wing, or canard, on the front. It is set to divert some air from the bottom, to up over the top. But the real cool stuff is the reverse wing design used on it. When the nose comes up from wind or waves, the reverse wing gets more laminar air flow over it, causing the negative lift to grow and put the boat back on the water. You can actually see it working! So, no air dams or strakes are used.

    I'll get a better video hopefully soon. My wife, as great a love she is, has no videographer talents! Her videos can give you motion sickness, LOL!

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    The video is great of your boat! It's getting at it. No porpoising, but some sponson dancing. Got a 4060 in there, eh? Do you think I'm on track with a 4050? I would rather spin the prop slower and use a bigger prop, the boat seems to like that better than high rpm.

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    Quote Originally Posted by CraigP View Post
    The video is great of your boat! It's getting at it. No porpoising, but some sponson dancing. Got a 4060 in there, eh? Do you think I'm on track with a 4050? I would rather spin the prop slower and use a bigger prop, the boat seems to like that better than high rpm.
    Given that my specific frame of reference in Sport Hydros are those in P Class [4s 10Kmah 34" length limit] my experience has evidenced that the popular three P-Sport Hydros { PT Stealth, Whiplash, FE 30 + some ML's I'm not too familiar with) all are around 30" and mostly run what started as Neu 2200KV 1Y's which have evolved into Castle/Neu's, Leo 4074's and TP 4060's. Easy 60+mph rigs ( My Neu 2200 1Y FE30 maidened at 68.xx mph with a M445). I'd consider the TP Power 4060 as a good choice for the DF34 - It'll get high 50's / likely more. Probably stay out of the danger handling zone. The 4070 in mine is overkill.
    Last edited by properchopper; 09-27-2017 at 04:29 PM.
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    2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
    '11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono

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    one of the quickest sport hydros i have seem running was a Whiplash- fe powered by a 1512 - 2650 kv on 4 s. he did try a 1515-2200kv but speed was not there.

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    All those hulls are wicked fast... I built the DF because I wanted a tribute boat to my brother's GP55. Those fast racing hulls have exaggerated sponson widths in ratio to the stern. They are also long waisted, so they don't look like full sized boats. I think the DF is too long and heavy to win... But still, I'm getting the itch to race. I might build one of those hulls just to race it, and leave the Littl' GP55 looking good! You guys gave me some great intel, thanks!

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    It's looking awesome Craig! and very nice work on the sponsons, mean looking indeed!

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    Quote Originally Posted by CraigP View Post
    All those hulls are wicked fast... I built the DF because I wanted a tribute boat to my brother's GP55. Those fast racing hulls have exaggerated sponson widths in ratio to the stern. They are also long waisted, so they don't look like full sized boats. I think the DF is too long and heavy to win... But still, I'm getting the itch to race. I might build one of those hulls just to race it, and leave the Littl' GP55 looking good! You guys gave me some great intel, thanks!
    Craig,

    In NAMBA the P-Sport Hydro class rules don't specify that the boats must resemble real Hydros, only that they conform to certain dimensional/proportional considerations.

    Here's some NAMBA P-Sport Hydros [FE30, Whiplash, PT Stealth& a Randy Naylor design] slugging it out in Az.
    https://www.youtube.com/watch?v=giN0xQeA8RE




    The 1/10 Scale Vintage, 1/10 Scale Modern and 1/8 scale class have to look like an existing full size / actually raced boat including engines and drivers..
    2008 NAMBA P-Mono & P-Offshore Nat'l 2-Lap Record Holder; '15 P-Cat, P-Ltd Cat 2-Lap
    2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
    '11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono

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    Scale Class . those sport hydros were going along very nice.

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    You guys mis read what I meant... I don't want to race Scale, just build a boat that I could make look like my brother's boat. I built the boat to do R&D on LiPo batteries and their possible commercial use in industrial designs. But I might be getting the racing itch! I was watching some FE30 boats on Utube, Tony, I think one of the video's was yours. They do have sponson walk and porpoising in the turns. My DF doesn't do that, but I currently lose more speed in the turns. But if it's a rough and windy day, I'm thinking I might hold my own! My modified DF will run some ugly water well...

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    not that i have these hulls but what i have seen in fe-30 size sport hydros , the quickest and best handling hulls have been either the ML Boatworks or the Whiplash. if you can buy or build one of these hulls i am sure you will be very impressed in what they do.

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    Quote Originally Posted by CraigP View Post
    You guys mis read what I meant... I don't want to race Scale, just build a boat that I could make look like my brother's boat. I built the boat to do R&D on LiPo batteries and their possible commercial use in industrial designs. But I might be getting the racing itch! I was watching some FE30 boats on Utube, Tony, I think one of the video's was yours. They do have sponson walk and porpoising in the turns. My DF doesn't do that, but I currently lose more speed in the turns. But if it's a rough and windy day, I'm thinking I might hold my own! My modified DF will run some ugly water well...
    Since you've concluded and posted that FE30's "have sponson walk and porposing in the turns" I'd like some equal air time. To begin with, I participated in the design of the FE30, tested prototypes until final design approval, singlehanderdly rolled them out to market, race-rigged more of them than anyone on Earth, and have raced both of mine from the very start (and my P-Ltd Sport, the very first production example is still racing and winning)with much success, + watched as many FE30's won countless races and Nationals. SO:

    They DO NOT have any inherent design characteristic that causes sponson dance in the turns. NONE. In a turn the outside sponson lifts from prop torque while the inside turn fin acts to to pull the inside sponson up / the outside sponson downand a tug of war is initiated as the sponson rear tips tap-dance over the racewater. If you're properly flying the hull this is what happens. Check out 36+ seconds in this vid &
    you might want to plug your ears
    https://www.youtube.com/watch?v=jC6I_ad8Isw
    (No park Rangers were injured during the making of this video)

    Not sure what you mean by porposing, but if prop lift, strut depth and angle, and fore-aft CG aren't adjusted to keep the a** from hopping, once maximum lift angle is achieved, gravity and the slowing from the front sponson area being wetted and slowing the boat down, the a** will hop. This can be tuned out but in typical racewater it's not a huge issue.

    The real test for your DF34 is to see what happens once sped up to P-Sport levels (60 to 70 mph). At 1/2 throttle my un-sponson modded DF34 doesn't exhibit any real problems either. Unleashed is a different story. Either way a DF34 rigged for P-Sport Hydro would be liked racing a Cadillac Escalade against a Formula 1 racecar given the competition from the current class winners.
    Last edited by properchopper; 09-28-2017 at 10:20 PM.
    2008 NAMBA P-Mono & P-Offshore Nat'l 2-Lap Record Holder; '15 P-Cat, P-Ltd Cat 2-Lap
    2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
    '11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono

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    Points well taken... No racing for the Littl' GP55! Didn't mean to get you riled up.. I think I said those are mean boats. You gotta race on the edge, to win..

  30. #30
    Join Date
    Dec 2015
    Location
    La
    Posts
    550

    Default

    Did you reinforce the hull anywhere? Those sponsons are killer love the metal work.

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