I'm building a water cannon that shoots out from the grill of my car

Here's what I have to work with: I'm powering the cannon with a 7 PSI carburetor fuel pump, which fits to 3/8 in. hose. I ran wiring thru the firewall and tore into my center console to affix an awesome red push button trigger below the center arm rest so that the passenger (or driver) can casually crook a finger and fire the cannon. For the hell of it, an orange LED on the dash lights up during firing unless the fuse is blown. The jet fires out of the center of my grill.

Everything is installed at this point, but the jet only shoots about 12 feet!

We were hoping for more like 30 feet, although I didn't bother with calculations when I started throwing this together. The nozzle is makeshift - just the nozzle from a windex spray bottle fixed onto the end of the injector hose with superglue and sealant. The nozzle aperature is basically a pinhole, and the path of the water through the injector hose terminates abruptly in a wall with this tiny hole. I'm thinking that the cannon would benefit from a slightly larger nozzle aperature and a taper into the nozzle as opposed to a sudden termination. Will this significantly increase range? What sort of household items, such as pens, can be fashioned into good nozzles? I'm also thinking of using a blowoff valve to build pressure before the cannon can fire - the pump seems heavy duty enough to survive working against some back pressure. A solenoid valve would also work, although more wiring and another button would be required. A more powerful pump would help, but funds are lacking.

Help me improvise and scavenge my way to finishing this project,Veeky Forums.

We want 30 foot range so that we can spray drunk frat boys and sorority girls standing/vomiting in the middle of the street after the bars get out. They usually won't move until you've nearly run them over. Otherwise, lots of innocent squirting of friends and people in convertibles.

Get a small 12v compressor, a small accumulator tank, and a single solenoid. Run the airline to the nozzle and allow the nozzle to pull fluid by venturi.

Then instead of water, use bleach. Fuck frat boys.

Also spray moped retards and bicyclists.

Hell, maybe even use gasoline and then put an electric ignitor on the nozzle. Fuck bicyclists

neat

Be sure to fill it with concentrated urine.

Hmmmm
Pony cum

Just go all out

shoot petrol at people

>cyclists
Especially these. Double points if it's in a downtown area.

Also might've been simpler to take 5 minutes to pull the hose off the rear washer squirter at the pump, reroute the hose and stick a small reducer on the end of it for extra range. Fill the reservoir with whatever, everything else is already wired and g2g

You'd probably be better just starting from scratch and building a PVC water gun using either some derivative of CPS or just straight compressed air, you could have the thing triggered by a 12v sprinkler valve that you can get from pretty much any hardware store, that setup should be able to easily get a decent volume of water over 30ft, the only caveat is that you'll have to pressurize the water tank with a bike pump every time you refill it.

I would rig up another washer bottle under the hood from the junkyard as a resevoir and use a 12v inline plumbers pump that goes down to an 1/8 inch nozzle to build pressure. Fill that shit with pure ammonia that you can get from those chemistry websites and spray those fuckers down. They'll smell like cat piss for a week. Frat boys can eat a dick.

>7 PSI
>30 feet
You need either a tighter nozzle, a pressure reserve, or a higher pressure pump. Seems like a waste of a Walbro/TRE though.

Plumb the pressure line into a section of 3"-4" PVC pipe with the ends capped with a check valve. The pump will fill this little tank to the highest pressure it can handle until the pump starts to cavitate. Then wire the switch to open a solenoid valve that vents the tank through your water line and out the nozzle. The bigger the tank, the farther it will go for a longer time.

Fuel pumps are rated on their max pressure. You need a restriction to build pressure. Imagine like putting your thumb on the garden hose. It goes a ton further when you close it off a little.

Add a pilot light for maximum effect.

kek

why not just use the air to pressurize the top of the reservoir and have the water spray out of a nozzle?

monitoring, I've always wanted a way to spray piss or break fluid at the cars behind me. was thinking about wiring in a windshield sprayer at the back of my car.

Kek

be like vw bugs and use spare tire to preesurize system

can you get a different container?
shitty plastic that thin will likely melt when it comes into contact with anything in the bay when your engine gets warm
if it doesnt melt you will be pouring EXTREMELY hot water on your target since theres no insulation at all

I did this for a while, just turned my windshield nozzles around one forward and one to the right for drive by, also have a hatch and face outward to spray tailgaters

As opposed to using an electric pump to provide pressure when you push a button!
How fucking dumb are you?!

Your going to have a hard time finding a pump that can provide both the pressure and volume that you need, going with a precharged system lets you get there easily and will be much simpler mechanically.

It would still use a push button to fire, your just opening and closing an electronic valve rather than starting and stopping a pump.

but how do you chamber the next round for when I only graze my ex?

...

Use semi-auto shotgun

Enjoy your loosened anus when some kike has you arrested for assault.

Add some servos so you can aim it around.