I had a thought the other day while thinking of something crazy i could do to my little redneck dakota. I said to my self, "What about a exhaust flamer." Now I understand the mechanics of how to do it. My only question involves a fuel source. I have the 2.5 TBI 4 banger, would the exhaust have enough material in it to ignite by a plug, or will I have to do an external fuel source?

 

You will need an external fuel source. Usually they use propane, but you may be able to tee off of a fuel line. Make sure the exhaust pipe is far away from any painted or chrome objects. Not just the outlet, but the last couple feet of the exhaust pipe will get red hot.

A guy near me had a flame thrower kit on his truck. Newer diesels come with a fuel injector in the exhaust before the DPF filter for burning off everything trapped in the filter, so when he removed the DPF and got 6" stacks, he put a spark plug at the top of each stack and wired the injector to a switch in the cab. It was really neat until the fuel pooled up in the exhaust pipe under the cab and it blew up, leaving him with a massive dent in the floor and a messed up turbo.

If you really want to do it, buy a kit and follow ALL of the directions. if the fuel source is not close enough to the end of the exhaust, this will happen to you.

 

This is a great question for www.google.com

 

The old school way to do this used to be an ignition cut off and a second coil, 2 switches.
One switch powers the coil which powers the tail pipe spark plug, then rev up the motor and flip the other switch which kills spark to the motor (flip it back on on the rev down so it doesn't stall). The unburnt gas from revving down will be enough to shoot small 12-24" flames.

 

This is my friends Rx-7. The rotary motor runs pretty rich and burns oil so all he had to do was run some wires from one of the coil packs to a spark plug at the end of the exhaust. When he revs it up, it will pop. Its carbureted so he is able to play with it all as well.
As well, in my Rx-7 without the spark plug, I can rev up the engine to about 3k, turn off the key then just before the motor completely stops, turn the key to the on position and like marcar1993 said, there will be enough leftover gas that it will ignite.

Haha also did this to my friends '67ish MGB and when he pulls out his throttle cable and lets it idle, it will shoot a constant flamethrower with no one even in the car. Sorry but I am too lazy too upload that video right now.

For your truck I would personally not recommend using a tee in your fuel line. Especially without some sort of a backfire preventive. It just seems stupidly unsafe too me. Maybe you could create a separate system which has a small pump that runs off of a switch. Still recommend putting a backfire preventive in though.

 

Another way you could do it is:
1: Go to your dodge dealership and ask them to change the timing on your truck to make it slighty rich when it runs "I did" and you won't need to run an external fuel source a.k.a propane tank or a jarry-can of gasoline and a make-shift sprayer out through your exhaust.
2: This is not the proper way to do it but definetly the cheapest for making your vehicle run richer, You can manually turn your distributor so it will run slighty rich when your drive, " I did aswell before going to the dealership, I had distributor problem, it would wobble about 1/16 of an inch and the truck would run/drive horribly, nothing like changing that in -40 weather. I would also like to not that this method is under your own risk and should be done with care.

Both of these method I have personally done to my truck without wanting to add the "flame thrower mod" I suggested them do it the amount of fuel it dumps out, I have witnessed and was yelled at because both time I managed to shoot out flames from just a super heated exhaust alone, first time was with method 2, I was at school and revved the engine to show off to my friends and a dumb-a$$ kid walked by my exhaust and it hit him. The method 1 was when I was at a party and we did the tow-go pull against my friends chev truck I believe it was a 1500, "I won" and rev it at high rpms it manage to shoot about 6-12 inches of flame multiple times. I believe that adding the spark plug to the exhaust would cause it to happen more frequently.

Also note, I am not giving you how to build a flame thrower exhaust here, I'll let other members on the site give it out to you, I am only giving a couple methods of running rich. Yes this will make your gas mileage not so appealing and you will notice raw fuel dumpage happen frequently reving at a higher rpm. Note that is lovely Canada, this mod is illegal and you will suffer a heavy fine/and possibly getting your vehicle towed.

So Merry Christmas and I hope this helps if you have any questions on my methods or what my vehicle is running/exhaust set up don\t be afraid to ask.

 

Pull the wires off of half your spark plugs. That should be enough fuel in the exhaust to ignite.

Sure, it'll run like crap, get 2MPG, and screw up your engine when all that raw fuel washes the lube off your cylinder walls. But the important thing is, you'll look super cool shooting flames out your exhaust.

 

Thank you to those of you who have contributed helpful information and know-how. I believe I am going to take the propane route. A small tank inside the cab with a regulator and a solenoid valve is my thoughts. Of course ignition will be a second coil. I will post some pics and a video whenever i get to doing it. Thanks again.