killiondesign

I am just going to put this out there and see if anone has some advice. I am currently building a project that is using a ryobi 31cc motor. I know some of you guys have years of experience with these motors so I posted in here. What I would like to be able to do is have flames shoot out of the pipes like on an old hot rod. I have made custom pipes that are very large and have some room to work on them. My first attemt at this was crude. I mounted a second magneto and ran that to a small spark plug I had tapped into the pipe. I got a good strong spark. I never got it to run rich enough to ignite the exhaust. Out of curiosity I wondered If I could just mist in some kind of flammable gas into the pipe. I drilled a small hole at the bottom of the pipe and used a small can of carbleaner with the red wd40 spray tube. I was ready to have this thing blow up in my face but to my suprise I never got any ignition. I know this is very dangerious to be messing around with but, I am confident I can do it. At one point I even (with the motor stopped) dumped some raw gas into the pipes and fried it up and still nothing. Cant have fire without O2 so, I thought I may not have enough fresh air to ignite. So far tests have beef fruitless. I really want to make this work so I will take any advice no matter how far out it sounds.

killiondesign

I guess I should spell check hu...lol

w8ye

My Feedback: (16)

In going to the hot rod shows, I noticed that the flames could not be sustained. They would have to let off the gas and let it build up and then kick the throttle wide open to see the fantastic flames come out. Some of the good ones could modulate the throttle somewhat and almost maintain a constant flame.

These guys seemed to using some kind of kerosene based secondary combustion aide.

WD40 itself is rather flammable. Try it again using real WD40. Some carb cleaners are not flammable.

Enjoy,

Jim

dirtypool

My Feedback: (6)

how far back to you have the spark?

the hot rod setup has the spark plug quite close to the end of the exhaust on the ones I have seen.

I cant believe that o2 is the only problem here. I doubt that these engines really burn THAT clean. Never done anything like this so I cant really say for sure.

Long pipe with a plug near the end, running rich, at or near full throttle would be the way I would try it. Also open the gap very wide on that exhaust plug. I would only try pumping flammables into the exhaust as a last resort (and maybe not even then). If you use a flammable liquid do not use exhaust pressure to pump it, only used a pump designed for that fluid. Do not pump any fluid at low throttle.

Good luck. If you get it working take some pics and post em for us.

Rob


Of course, this is all theoretical and for discussion purposes only and never to be tried in real life. The comments above are not the opinions of RCU or Ryobi or even me. Who said that? I dont know what you are talking about. I'm outta here!

dirtypool

My Feedback: (6)

[link=http://www.gotflames.net]www.gotflames.net[/link]
[link=http://www.flamedexhaust.com]www.flamedexhaust.com[/link]
[link=http://www.flamingexhaust.com]www.flamingexhaust.com[/link]

Try these, maybe they can help as well.

w8ye

My Feedback: (16)

"Flamed Exhausts work by bypassing your engines spark plugs and fuel release to temporarily change the receiving source to your exhaust pipe allowing gas to pass through and create an ignitable fuel source."

An ignition enterupter? This explains why the flames were not sustained. That the engines seemed to be throttled. The ignition was interrupted to make a oxygen rich fuel mixture at the exhaust pipe?

Jim

killiondesign

Yea, I knew how it worked on cars. I wonder if there is some kind of interupter switch I could build onto the plugwire to kill the spark for a split second to get it to work in a similar way. Good Ideas guys. Keeps my gears turning. By the way, Im suprised no has asked what kind of project this is. ::evil grin:: Hows about the fastest flame throwing blender in the south. lol...[img][/img][img][/img]

dirtypool

My Feedback: (6)

HOLY MARGARITA-TA's!!!!

dirtypool

My Feedback: (6)

Since you are not worried about radio interference, you could have a spdt switch on the magneto kill posts. when the switch is in normal, it grounds the flamethrower mag, when the switch is in "flame" it grounds the spark plug and allows the flames to fly.

you would probably want it to be a pushbutton where you can modulate it (on-off-on-off-etc) so the engine will not die.

I dont know if that harms the magnetos by keeping them grounded for so long.

Anyone?

dirtypool

My Feedback: (6)

Arent you afraid that the exhaust flames will ignite your margaritas?

(just kidding)

Rob