300/440/550 550sx Hull Modernization Build

Yea keeping the 550 reed motor in it - it will be slightly modified but still the same block.

Not planning on wasting my time making a mold from a 550 ski lol sorry - I'd rather just start from scratch and make a plug from laminated 2" sheets of XPS! Having made a hood, and knowing that I could make a nose and design a hood opening on a top deck - it would only be worth it to start from scratch and not be forced to include any of the design flaws of a 550 hull!

I'll hopefully have the nose and tray fully reinforced, the nose attached, and the tubbies laid out by this week. Goal for the weekend coming up is to have all major glassing done! Then I need to start finish work which will easily take a week to make it look half decent.
 
its just a pjs viper engine thats stock from pjs with some pump and hull mods... still a very nice ski.. i recently got the same engine in my ski and am trying to get the carbs dialed in.. i can already tell its a beast for a 550 engine...
 
great build. Im starting something very similar right, just making space in the basement atm. You tackled pretty much all the hull mods i want to address, just a little differently. I want to try to figure something else out for the nose though.
 
This is a really cool build. I would definitely put a bigger pump in there at this point in time though.

Sorry - I can't justify spending over $2000 on this build - which it is fastly approaching. I'm pounding my head into the wall everytime I go to work on this now thinking.... why didn't I just buy a superjet?

It's staying a 550sx - so I can be eligible for competing in "coolest 550 ever" contests lol.
 
The hull with hood has to be around 75 pounds right now. I could be wrong tho I haven't scaled it. But it weighs about as much as my dog does and my dog is a fat ass.
 

N2 H2O

Previously Tbone550
Location
Charlotte, NC
I'm pounding my head into the wall everytime I go to work on this now thinking.... why didn't I just buy a superjet?

That's where I got on my build and I didn't do nearly us much as you are...so I said screw it, parted it out and went and bought a superjet!


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That's where I got on my build and I didn't do nearly us much as you are...so I said screw it, parted it out and went and bought a superjet!

At this point I just look at it as another engineering college course - tossing thousands away and learning something new! only this one I get to keep all the test material afterwards and ride it.
 
"Day" 26....

Sick build! Subscribed

Your build turned out pretty good as well!

Well I made some more progress tonight - although it usually doesn't result in as much feeling as accomplishment as does laying up fiberglass to form a new part of the hull, sanding is a very crucial step!!

I sanded the tray, hood inside, and the new nose piece. I needed to prep all of these for their reinforcing glasswork that I'll be doing tomarrow....

Nose:
As you can see - I contoured this internally to try and achieve a stronger design for the pole mount. I plan on doing overall 2 layers of 1708, and an additional 4 layers of 1708 right under the pole mount (square part of exposed glass in the middle)
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I put the engine back in for a mock up under the hood - and much to my amazement I have A LOT of room (could of kept the K&N setup just about!) so I may be looking for a stock superjet flame arrestor if anyone has one!!! I'll pay up to $40 shipped if it's immaculate.
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So in preparation for tomorrow - I got the less than fun part done tonight - templating!! 1708 will be used on the nose and tray areas, and 1208 will be used to reinforce the hood.
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Yep - a :):):):) load of templates! It may be tedious, but it makes glassing a breeze!~

And my turf order arrived! Going with grey molded diamond B-stock, and orange cut diamond.
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I also ordered 26mm and 8mm PLUSH which will be sorted out around the tray in a manor I have figured out already.

I'm going with the molded diamond for the floor and footholds since they will see the most abuse. I'll use the orange on the tray walls (wrapped around to the outside walls), the chin pad and the bond rails. I'll have a good amount left over so I may put proper footholds in my 440 and re-turf it as well? we'll see!
 
I can see the light...

The light at the end of the tunnel is nearing!

Got all the reinforcing done now! just a few little tidbits here and there...

It all started with templating the :):):):) out of my last few yards of 1708. Gonna miss that stuff! Good thing my buddy lent me his leftover 3-4 yards to do the bond rails! I absolutely abhor 1208 - that :):):):) is horrible and flakes apart like an overcooked fish dinner! I'd much rather sacrifice the weight savings (that is actually arguable, since you may need two layers of 1208 to equal the strength of 1 layer of 1708, but 1 layer of 1708 will be lighter than 2 layers of 1208!)

Anyways...
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The finished hood (11 pounds before final sanding...)
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-I think I probably went overkill on reinforcing the hood, but it really is strong as :):):):) now!

And tray
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-The tray has 4 layers of 1708 in the foothold and main tray area, and I added another 2 right under the foot strap location for more material for the inserts to bite into!
-I may have mentioned it already - but adding those triangular wedges to join the rear gunwales to the front section increased the stiffness about 1000000%! They are practically immobile now were as before if you tried to squeeze them inward or outward you could to some extent!

And finally the nose being attached!
IMAG0796.jpg

-A nice layer of peanut butter cab-o-sil/epoxy mix will hold it in place after it cures, and I'll internally bond it with a layer or two or 1708 (Top deck to bottom deck with a 3-4" wide strip).
-The floor under the pole bracket mount is appx. 6 layers of 1708 thick. Should do the trick?

Everything is going well - didn't get my tubbies laid out yet, but that's what I'll do tomorrow. Thinking of possibly abandoning the 2 layer design to emanate the newer designs with rear rocker - reason being is that I'm only going to use 2 layers of 1208 on the tubbie, and if I do the whole side that will leave the side relatively soft since there will only be foam under the glass. I'm thinking of just making a single longer tubbie that has a stepped shape about halfway to sort of imitate the rear rocker.

Still definitely adding a matrix/superfreak bond rail though! This will hopefully help imensly with handling?!

Also I will be adding my 5/16" fiberglass rod ($5 item from McMaster!) to the bottom to make deeper chines! I think that will be a nice improvement - not overly deep, but along the lines of a superjet/superfreak. Being that they are structural fiberglass and not wood, I'm more confident that this will still be a good beater ski and not one that needs babying!
 
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