I"M BAAACK ........

[Novicaine]

Here is the Fast Track vehicle.... fairly fast on land and water. But I don't think it'd handle rocky shallow rivers.

https://www.youtube.com/watch?v=cWKbS99fBH4

 

[PSG-1]

Awesome boat. A little slow on the water, actually looks faster on land. I want to see if I can achieve the opposite effect with my design, fast on water, but still able to move at a good clip crossing a dry shoal at low tide.

 

[scubapro820]

That thing was neat!! when I get a chance i will draft my idea for this project.... although at the moment im in the process of building a new house so I wont be able to afford to build it anytime soon. iva actually been thinking of doing more to the boat I have now Im not happy with 38-42mph anymore I think ive come up with some ideas to achieve 50mph

1 aluminum tigershark 900 engine mounting bracket vs the 45lb 3/8'' thick steel plate one
2 agm or L-Ion cell under 10lbs vs the 50lb lead acid marine starting 1000cca bat I have.
3 the stupid half arsed engine box I made bc I was broke is made of wood will be replaced with an aluminum compartment
4 reduce pilot house profile be 12''
5 send impeller to impros for a custom pitch still have the top 1/4 of my throttle that just gives me 7800 rpm with no speed increase
6 mess with the water pickup design

if that doesnt get me 50 im switching from a skat trak swirl to a straight cut design for top end I think that the swirl costs me 3+ mph
I can ditch 100lbs and alot of wind resistance I think what do you guys think?

 

[PSG-1]

That thing was neat!! when I get a chance i will draft my idea for this project.... although at the moment im in the process of building a new house so I wont be able to afford to build it anytime soon. iva actually been thinking of doing more to the boat I have now Im not happy with 38-42mph anymore I think ive come up with some ideas to achieve 50mph

1 aluminum tigershark 900 engine mounting bracket vs the 45lb 3/8'' thick steel plate one

I never compared the weight between the steel mounting plate and the aluminum one, but the 2 were interchangeable between the 900 and the 1000, the motor mount holes are in the same positions, and the holes in the plate that bolt it to the engine are exactly the same. I do know that the aluminum plate is quite heavy and thick, though, but I'm not sure about its exact weight.

3 the stupid half arsed engine box I made bc I was broke is made of wood will be replaced with an aluminum compartment

It'll be more durable, and lighter in weight. If you form it by braking, the bends will give added strength. If not, then using some aluminum angle welded to the inside will help stiffen the structure.

4 reduce pilot house profile be 12''

This will make a difference. I have a T-top that I use on my jetboat in cold weather, it has a full-height windshield, as well as side window panels, there is at least a 2-3 MPH difference in the top end when compared to the standard-height windshield I usually have on the boat (4 bolts is all it takes to switch out)




These are older photos, as the sponsons are on the boat, taken back around 2006, about a year after the boat was built.

5 send impeller to impros for a custom pitch still have the top 1/4 of my throttle that just gives me 7800 rpm with no speed increase

Experimenting with pitch can either give good results, or crappy ones.

Another option you should consider is a "Wet Wolf Adjust-A-Thrust Nozzle" It uses a spring loaded shuttle that responds to varying water flow through the pump, and it can give top end gains of around 1.5 MPH, as well as better hook-up and loading in choppy water. I started running one on my boat a few months ago, it does make a difference. Better hole shot, better top end, and better hook-up in the chop.

6 mess with the water pickup design

You mean the intake duct? I may have already asked this (I suffer from C.R.S. sometimes) but, have you tried a top-loader grate? If so, you may be able to experiment with the rake angle of the top loader scoop on that grate where it's not so steep, which should remove some drag.

You could possibly cut the rake loose from the longitudinal tines, using a thin-kerf recipro saw blade, then, drill a hole through either tine, for a screw, and then drill and tap into the sides of the rake/blade itself.

This way, you could position it, and lock it down, and experiment with varying angles, without having to cut and re-weld it every time. Once you're satisfied with the position, then weld it.

if that doesnt get me 50 im switching from a skat trak swirl to a straight cut design for top end I think that the swirl costs me 3+ mph
I can ditch 100lbs and alot of wind resistance I think what do you guys think?

I think you're on the right track. Not sure about straight cut vs. swirl impeller as far as top end. I do know that swirl impellers are better in rough water, and they're less susceptible to being fouled than straight blade impellers. But as far as which one gives better top end, I'm thinking probably the straight edge.

 

[scubapro820]

You're right about the swirl having better hook up and not getting fouled by weeds but it traps wood chips really bad like a door stop and starts cavitation at 4k and 3mph lol hookup has never been an issue yet / v hull the steel plate is like 40-45 lbs it was used in the tigersharks with the m.a.d. multi Angle deadrise hull as ballast bc they sat higher and also why they were famously tippy I don't need ballast so I want to ditch the steel . I think reducing the profile will make it faster by a bit buoyancy is a plus if I drop 100 lbs I can add cargo too. Btw how.did you make the sponsons ? Rigid inflatable ? I hope for 3-4 mph by impeller pitch I think its 19/21 I want 2+3 inches more it should bring my rpm down to 6500/6000

 

[PSG-1]

No way I could use inflatable sponsons out here. Not with all the barnacles and oysters I encounter. :shock: :shock:

The sponsons were made from .050" X 10" aluminum irrigation pipe, which was notched, and welded to follow the angle of the boat, and then a cap welded to either end, made from 1/8" plate. Then I used aluminum angle clips that were welded to the sponsons, and riveted to the gunwales of the boat.

Here's some photos:


The raw material, .050" X 10" irrigation pipe, from Mid-Atlantic Irrigation



Starboard side completed, port side not done yet:










Completed:






It sure was a PITA welding this thin material, especially getting it welded air-tight. On the starboard side, I didn't use chill rings on the inside of the seams. Having dealt with that, on the port side, I used chill rings, which made welding a helluva lot easier.

Anyhow, once I got it done, it held pressure, all the way up to 15 PSI, which is really overkill, it only needs to be about 2-3 PSI, but this just goes to show that it would hold that amount of pressure:

 

[Tinklespout]

Nice! That is too cool.

Do you think I could use PVC pipe? I can't weld.

Im considering filling them with foam or nothing. Why did you pressurize?
Kim

 

[PSG-1]

Nice! That is too cool.

Do you think I could use PVC pipe? I can't weld.

Im considering filling them with foam or nothing. Why did you pressurize?
Kim

You could probably use PVC pipe, the majority of the run down the gunwale is going to be straight. However, you might run into some issues when you get amidships, as the gunwale begins to curve toward the bow. You can see how we had to cut, notch, and weld to deal with that. You could possibly heat the PVC enough to make it pliable, and bend a gradual radius in it to make that curve, I'm not sure how that would work out.

Your other issue would be how to make a system of being able to attach the tubes to the boat. Some type of brackets or clamps that will attach to the gunwales.

Filling with foam would give you some added buoyancy in the event of the tube having a leak, or knocking a hole in it.

I pressurized, because as long as there is positive pressure, you know there's not a leak, and therefore, no water being in the tube. As the photo shows, each tube had a PSI gauge that read up to 15PSI, and these gauges were located amidships, on the top of each sponson, where I could easily see them from my position at the helm.