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derpid
11-13-2019, 01:46 PM
Soooo id like to hear some feedback from guys who have added a pad or lifting strakes, or both to a vee hull. was it a terrible idea? did it work out as planned? would it be better to add the strakes over the pad or the pad over the strakes? any advice?

My boat only has one set of full length strakes (out of the 3 sets total) and a flattened/ rounded vee the last 5 ish feet of the hull. im wondering if its even worth going down the road of adding a pad or running the other strakes full length to help it fly more, or just accept it as she is.

Boat is a '92 seaswirl spyder 188

LakeFever
11-13-2019, 01:54 PM
I considered this as well and what I discovered is its a LOT of work, and a lot of testing and likely a few reworks to get things working at high levels. Doable? Absolutely. Worth it? For me no it wasnt. Bought a hyrdrostream, then another... lol

derpid
11-13-2019, 02:08 PM
im thinking it might not be worth the time and money to go down that road either, the boats gonna need a new floor and stringers soon so thinking about going all out when i do. maybe not so much the pad but i think running the rest of the strakes full length would be worth it????

derpid
11-13-2019, 02:14 PM
Not alot of lift at the centre of the hull, the centre most strakes terminate about half way down the hull so most of the time i believe it just kinda runs flat on the rounded vee when i get it up there.

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David - WI
11-13-2019, 02:28 PM
The Tunnelboat Design program from Aeromarine Research has a 19' vee hull with a pad already all input... be a lot quicker & cheaper to make changes in the sim; if you're into that kind of stuff.

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Gordon02
11-13-2019, 04:00 PM
Strakes and pads lift the hull -but, only if there is enough hydraulic pressure to lift the weight. You don't mention the speeds, horsepower, or weight so we're all guessing. The vertical surfaces actually increase the wetted surface of the hull if there is insufficient speed to take advantage of the pressure. I've owned 20+ boats through the years and most of those had pads. Very few of those actually needed or benefited from having those pads. My experience with these different Pad-V's is that it would take 60+ mph for any of those to start climbing up on the pad. Only one of my boats could actually support it's full weight on it's pad like a ski. My Allison is still very wet at 60 mph.

Adding a pad to a boat that will run 55 mph without a pad won't suddenly go 65, 70, or 75 mph with one. Gordon

derpid
11-13-2019, 04:08 PM
Strakes and pads lift the hull -but, only if there is enough hydraulic pressure to lift the weight. You don't mention the speeds, horsepower, or weight so we're all guessing. The vertical surfaces actually increase the wetted surface of the hull if there is insufficient speed to take advantage of the pressure. I've owned 20+ boats through the years and most of those had pads. Very few of those actually needed or benefited from having those pads. My experience with these different Pad-V's is that it would take 60+ mph for any of those to start climbing up on the pad. Only one of my boats could actually support it's full weight on it's pad like a ski. My Allison is still very wet at 60 mph.

Adding a pad to a boat that will run 55 mph without a pad won't suddenly go 65, 70, or 75 mph with one. Gordon

currently running 65mph with a G1 Evinrude 225HO with 14" setback and best results with the propshaft around 3" bellow the "pad" and weight in at just shy of 3500lbs boat motor and trailer.

derpid
11-13-2019, 04:14 PM
The Tunnelboat Design program from Aeromarine Research has a 19' vee hull with a pad already all input... be a lot quicker & cheaper to make changes in the sim; if you're into that kind of stuff.


looks like a cost effective way to see if there is any benefit to adding a pad without actually doing it. I like!

Gordon02
11-13-2019, 04:30 PM
A pad for 3,000 lbs of boat, fuel, and passengers is way above my pay grade...

derpid
11-13-2019, 04:32 PM
in other words, probably not worth the hassle?

David - WI
11-13-2019, 04:55 PM
Just quickly changing the power, weight, setback & height, lower unit, etc on the "demo" boat to resemble yours... 71.0 mph without the pad, 71.9 with. Obviously this doesn't match your exact boat, but the difference with or without a 12" wide pad looks small.

derpid
11-13-2019, 05:06 PM
yeah there are other factors to include but i imagine it would still compute to a difference of not really worth it in the end. a simple repower to a 300 would likely get me 70-75 and thats something that can be done with ease.

derpid
11-13-2019, 05:48 PM
It has good overall manners at WOT, just wish it would “fly” a little better. But every hull has its limitations I guess.

Gordon02
11-13-2019, 06:14 PM
Here's one of my favorite pad flying photos......biggest difference is 2,000 lbs.

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derpid
11-13-2019, 06:28 PM
lol, yep. bit harder for the heafty ones to fly. but it looks soooo much cooler when they air out like that. is that an Allison?

Gordon02
11-13-2019, 06:40 PM
Yes, Allison. I think it's an XR2001 or perhaps a SS2000. One weighs 650 lbs, the other 900. Mine is a XB2002 and weighs 1,250 lbs with the short-shaft Merc.

derpid
11-13-2019, 06:56 PM
very nice. i cant compete with my fatt 19ft, but its purdy and i like the layout.
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Will hedrick
11-13-2019, 09:22 PM
Yes, Allison. I think it's an XR2001 or perhaps a SS2000. One weighs 650 lbs, the other 900. Mine is a XB2002 and weighs 1,250 lbs with the short-shaft Merc.

My xb02 is a little heavier than that, prob. A 100 or so with the etech

Greg G
11-14-2019, 05:57 AM
in other words, probably not worth the hassle?


For what you have correct. not worth the hassle. Post a better high res picture of the keel.

derpid
11-14-2019, 01:25 PM
lets try this

LakeFever
11-15-2019, 09:08 AM
Try some different props that thing is wet. I can’t see why you can’t get a lot more air under it with set up changes

derpid
11-15-2019, 10:03 AM
I’ve tried every prop I can get my hands on over the last two years except for a full on cleaver. But with a L1 gearcase a guy can’t really surface it enough to see the benefits (also kinda scared she might get right sideways if I do). Tried messing with less set back this summer with no success, it would likely benefit from 2-4 more inches of set back but I was not in the mood to order a 10 or 12 inch bracket this summer and re rig for the 7th time to see lol.
This is kinda why I was thinking about modding the hull design with either more strakes or a pad, 14” setback should be enough to air it out a little.....

derpid
11-18-2019, 05:30 PM
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Little better photo, but she’s still pretty wet.

Will hedrick
11-18-2019, 05:49 PM
You said you were 3" below pad. Keep an eye on your water pressure and come up in 1/4 to 3/8 increments. How far have you brought it up before?

derpid
11-18-2019, 06:04 PM
running hyd jackplate w/ water psi gauge so ive tried every height i can without sacrificing water pressure. it seems to loose the walk with higher engine heights but it doesnt seem to lift as well. if i remeber corectly with where i have it bolted curently i can jack all the way up to 1" above, maybe a tad more. it just seems to settle the best around the 3ish inches bellow the pad. running higher doesnt seem to do much more than make a cooler looking roost.

Will hedrick
11-18-2019, 06:24 PM
running hyd jackplate w/ water psi gauge so ive tried every height i can without sacrificing water pressure. it seems to loose the walk with higher engine heights but it doesnt seem to lift as well. if i remeber corectly with where i have it bolted curently i can jack all the way up to 1" above, maybe a tad more. it just seems to settle the best around the 3ish inches bellow the pad. running higher doesnt seem to do much more than make a cooler looking roost.

I was curious, I was running a coned m2 and have recently got an L2 factory, m2 1/4 below and the L2 I'm prob 1 1/2 to 2 " below for w.p. reasons, I will cone it eventually , the L2 is a faster unit i.m.o., your L 1 have 1.71 gears by chance?

derpid
11-18-2019, 06:26 PM
i was mostly currious on the value of adding a pad to an existing hull, it would likely help it fly better in the long run but it seems like that might be a very long and costly run to get it there. as far as setup goes i just kinda got tired of tweaking last summer and just let it be and enjoyed the water at 65mph. i believe that a tad bit more setback is the key (as ive ruled out less) but going further than 14" on the OG transom didn't seem like the right idea and it just barely fits in the shed as is lol.

Will hedrick
11-18-2019, 06:32 PM
Lol least its garage kept, I would agree with Gordon, cost/time would be great for not much gain,

derpid
11-18-2019, 06:34 PM
I was curious, I was running a coned m2 and have recently got an L2 factory, m2 1/4 below and the L2 I'm prob 1 1/2 to 2 " below for w.p. reasons, I will cone it eventually , the L2 is a faster unit i.m.o., your L 1 have 1.71 gears by chance?

running the 1:87 gears to my knowledge.

Will hedrick
11-18-2019, 06:38 PM
Nice there was a short time they built them with 1.71, almost like the brp. Holy grail, hard to find, people not want to sell them when they get them

derpid
11-18-2019, 06:38 PM
Lol least its garage kept, I would agree with Gordon, cost/time would be great for not much gain,

not a big fan of storing boats outside. drives me crazy when i see the neighbors do it.

be much easier to repower to a 300 to go faster (which may happen, see how life goes)

Greg G
11-18-2019, 06:59 PM
You mentioned you have tried many, many props. Did you try either a Solas Scorpion or a Merc Rev4 ?

derpid
11-18-2019, 07:14 PM
The scorpion is my current and best prop. Also tried rev4 and didn’t like the crabwalk it gave me.

Greg G
11-18-2019, 07:22 PM
Well the Scorpion is one of the best "lift the whole dang boat" props out there. Is that picture you posted where the hull is super wet when you are running the Scorpion?

derpid
11-18-2019, 08:25 PM
Yep running a scorpion in both pics.

Greg G
11-18-2019, 08:26 PM
Houston ............. we have a problem!

derpid
11-18-2019, 08:28 PM
Now you can see why I was considering a pad lol

Greg G
11-18-2019, 08:31 PM
It won't work IMO. You have other things going on if you are that wet out of the gate.

Greg G
11-18-2019, 08:33 PM
And btw, you already have a Delta Pad from the looks of it. I would take straight edge to it and a laser and ensure it is totally plum and flat etc. then after that start to look for the next issue.

derpid
11-18-2019, 09:49 PM
Maybe I need to go back to the basics..... I have alot of positive trim left to go up but always back out due to the walk. Might be worth going back to square one and attempting to balance the boat with counter weight and driving through the walk in the atempt to wet less of the hull. If you think of trim gauge like a gas gauge, I run at a touch under half and it doesn’t walk, if I get past half and up to 3/4 or approaching it starts to walk bad and it’s hard to drive through.

David - WI
11-19-2019, 08:56 AM
Don't underestimate the effect of more horsepower....it doesn't just make the boat go faster, it (usually) makes the boat go faster without needing as much trim (and setback) to get the hull up out of the water.

I had a chance to try a +50hp powerhead on my Checkmate and it went from 75 mph with 1 person & the nose in the sky... to mid-80's running almost "flat" with four people.

When you're underpowered you're always struggling to get the hull out of the water. FWIW.

LakeFever
11-19-2019, 10:58 AM
Maybe I need to go back to the basics..... I have alot of positive trim left to go up but always back out due to the walk. Might be worth going back to square one and attempting to balance the boat with counter weight and driving through the walk in the atempt to wet less of the hull. If you think of trim gauge like a gas gauge, I run at a touch under half and it doesn’t walk, if I get past half and up to 3/4 or approaching it starts to walk bad and it’s hard to drive through.

I know this pain my old boat was super hairy at speed but needed a lot of trim to get there. It liked the motor deep in the water and SRX prop with a ton of trim made it scoot realllll well but two hands on really working the heck out of it.

derpid
11-19-2019, 11:57 AM
Don't underestimate the effect of more horsepower....it doesn't just make the boat go faster, it (usually) makes the boat go faster without needing as much trim (and setback) to get the hull up out of the water.

I had a chance to try a +50hp powerhead on my Checkmate and it went from 75 mph with 1 person & the nose in the sky... to mid-80's running almost "flat" with four people.

When you're underpowered you're always struggling to get the hull out of the water. FWIW.

i don't think im under powered, but going to a 300 is not off the table.

derpid
11-19-2019, 12:00 PM
I know this pain my old boat was super hairy at speed but needed a lot of trim to get there. It liked the motor deep in the water and SRX prop with a ton of trim made it scoot realllll well but two hands on really working the heck out of it.

i always got sketched out and didn't put too much effort into getting the static balance right before trying to fly the nose. this may just end up being one of those hulls that needs a sandbag in the passenger seat to scream.

LakeFever
11-19-2019, 12:18 PM
65 certainly isn't slow either and is probably a white knuckle experience for first time passengers. It gets boring to our kind after a while no matter how high the speed we seek more eventually. This is why its great to own multiple boats to suit the mood of the day

derpid
11-19-2019, 12:25 PM
gf doesnt cry anymore lol, but she needs to gain 120lbs to balance me out if im using her as a counterwieght.

LakeFever
11-19-2019, 12:27 PM
Careful what you wish for :leaving:

:D

derpid
11-19-2019, 01:01 PM
dont you hex me lol

tnelsmn
11-24-2019, 01:19 PM
Hate to link to another forum but I feel it applies here. Ron added a pad to an old Glastron. But with the current power he has its not enough to get the hull up and on the pad. Food for thought.
http://hydrostreamforums.com/viewtopic.php?f=6&t=3609

Jimboat
11-24-2019, 02:57 PM
Soooo id like to hear some feedback from guys who have added a pad or lifting strakes, or both to a vee hull. was it a terrible idea? did it work out as planned? would it be better to add the strakes over the pad or the pad over the strakes? any advice? Boat is a '92 seaswirl spyder 188

Adding a pad to a vee hull can provide some performance benefits, but doesn't necessarily help on just any existing vee setup, as it depends on several factors. (Some hulls the mod can help, but others it may not). In any case, the pad modification requires that the pad be specificallyy sized for the existing vee hull design, weights, power, etc. The required pad sizing (length, width, height, shape, edge design) to support sufficient Lift to make a performance benefit is the key to successful vee pad mod's that will actually improve performance and also exhibit sufficient dynamic stability. There's also some 'technical' issues to consider (eg: height optimization), since you're starting with a vee hull and 'adding' a pad, rather than integrated pad.

Here's a couple of articles that gives some explanations...

"How a Vee-Pad works (https://www.screamandfly.com/content.php?219-The-Bottom-Line-How-a-Pad-Makes-a-Vee-Hull-Faster)"

and "Pad Sizing (https://www.aeromarineresearch.com/download/PBR_MarApr2018.pdf)"

also... here is a video of VBDP software comparison of "Pad vs No-Pad" analysis (https://youtu.be/-bB1OG1TAZQ) example. (video is using an older version of software, so it's missing some features of newest version, but process still the same).

tnelsmn
11-24-2019, 05:37 PM
Jim- "How a V Pad Works" link isn't working.

Jimboat
11-24-2019, 06:01 PM
Jim- "How a V Pad Works" link isn't working.

OK, i think it's working now.

(it' one of the articles that i did for Scream & Fly... more here (https://www.screamandfly.com/content.php?5-performance-tech).)