300sx/superjet hull build -DONE... they're never done

schicks

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West Michigan
Figured I’d do a build thread on this one. I bought this because I am to cheap to get into an aftermarket hull and I wanted a short play ski on hand and frankly building one sounds more fun than working for 6 months to buy one. Have done some fiberglass in the past, but not quite to this extent; but with any luck you should see a running and maybe flipping ski next summer and most likely before the Blunder jet thread is completed:) Should be a fun ski when done.
It’s a 300sx hull that has had a sn superjet bottom glassed in. Its all superjet bottom from the pump bolts up to the motor mounts and will have a superjet firewall. The rest is up to me…nose, tubbies, rocker shape, rails, foot holds, tray, pump
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First on the list was clean up, more trimming, and of course sanding and shaping. It had been sitting outside for sometime before meeting me. 300sx smc is paper thin!
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I hope to finish the bottom before the snow flies. After shaping the front foam which rests on the original 300sx bottom, the plan is to lay glass on the duct tape to get the shape I want, remove it and cut out the rest of the 300sx bottom, glass in the formed piece and build it up from the inside. Removing the rest of the 300sx will save weight and give me more space for water box and gas tank mounting. The strikes are off in the pic, it has been corrected and final shaping can happen later. No tubbies for now, I have yet to ride a ski I like with tubbies.
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Next, I figured ‘why not’ and cut the pump cavity out. More water you throw, the more thrust you have. Not sure if my tinfoil technique has ever been used, but it sure beat shaping/cutting foam and I think its going to work just fine! Gotta have a little rickter in my 300.
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Also working on shaping the back. More work to do here. Hope to glass some this weekend.
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schicks

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Location
West Michigan
i dont think this will end up under a 125 lbs, but im good with that, the dang hood has to weigh 25 lbs! Just wanted to build something shorter than my -3 SJ that I can toss around. Have a ported 701 going in it, 144 pump, and if i like it, I may put the JM BB in er'. I have most of the parts on hand, will only be buying a handful of odds and ends to complete it. Bought it from a riding buddy and figured it would be fun...plus my end paint scheme is what really prompted me to buy it :)
 
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schicks

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Location
West Michigan
Got the nose piece mold done and the remaining 300sx nose cut out. The nose piece fits perfect with the custom middle finger! Not sure how or if I should trim the bottom hull depth down. Any ideas/suggestions? leave it? change it?
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300sx16.JPG any suggestions?
 
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schicks

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Location
West Michigan
got most of the bottom glassing done on saturday and did some riding sunday. Glassed the pump cavity, rear, nose piece 1708, rails 1708 and thin 5oz, keel reinforced with 1708. Still hope to foam and glass the nose yet, getting cold here.
need to mount a pump, intermediate housing, and motor to make sure everything lines up nicely before glassing the firewall in. Let me know if there is something else i should check or if you see something i missed. Was thinking about rockering the rear corners similar to the xft skis, but i think it's narrower than a superjet in the back already so it may not be needed (will confirm). Also wish i would have done the water intake track fingers bigger...
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schicks

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Location
West Michigan
got the bottom sanded good enough for now. Flip the ski over and started grinding and sanding the engine bay and rear for glass. While bolting in an engine, mid shaft housing, and pump to verify alignment. Problem that I see: this ski has an old 1990 square nose bulkhead which had the 650 motor and the subsequent small intermediate housing. Not sure if I should pull that bulkhead out and either modify the current one for the bigger housing or pick up a new bulkhead setup for the bigger housing?? Or should I not worry about it? I don’t really plan on running anything bigger than a big bore in this ski. Any thoughts or experience???
 

schicks

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Location
West Michigan
Progress has been slow, still trying to get heat ran in the garage. As soon as I have somewhere above freezing to lay glass, I will reinforce the entire inside engine bay area and tray, as well as finish the firewall.

I did take some measurements of the 300sx compared to my stock length SJ. The ballpark measurements are:
2003 SJ - 21" wide at the back by the ride plate
-about 86" in total length back to front
-about 56" from the back to where bottom begins to curl up to the nose

300sx -23" wide at the back
-76" of total length back to front
-about 48" from back to where bottom begins to curl up to the nose

so roughly 10 inches shorter than a superjet and a couple inches wider, plus more abrupt rocker to the nose following profile similar to a SJ but deep keel.

Also confirmed the motor/int housing/pump all aligned. I am going to mock it all up again and make sure that a b-pipe will fit without issue and make sure that I locate the firewall so the ebox wont have clearance issues with pipe or motor. Here are some picks from the mock up.
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Here's your waterbox for the ski Phil
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Edit: there's your driveshaft and pump stator too haha
 

schicks

Karma Enforcer
Location
West Michigan
This looks like the 300sx project skibum had a year or two sho... he sold it, and wow, its just now getting worked on?

I think you're right. I noticed that to when I was doing some research before buying it.

Made good progress in the last couple weeks. Will post pics soon.
 
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