Building the Humungus machine

[HUMVEE Driver]

Yep, I got your message. I'm going to give you a call about 5pm your time today... that is, if I can figure out how to call you there!

HUMVEE Driver

[HUMVEE Driver]

So I was watching The Road Warrior, and the scene came up where the Bad Cop hits the nitro on the Humungus Machine. What hit me (this time) was the flames shooting out of the exhaust stacks. That got me thinking...

I did some research on flamethrower exhaust kits. Turns out there are two kinds. They both use a spark plug inside the pipes to ignite something to get the flames. With one kind you adjust the carb so it's running rich, and gas passes through everything and ignites to get the flames. You get big flames, but it messes with the engine. I don't like that part at all. I don't want it breaking down or whatever. With the other kind, it ignites the flammable gases in your regular exhaust. But the trade off is that the flames aren't as big.

So... I'm going to be having this done to the Machine. It's going to have a switch on the 'dashboard' so I can turn it on/off and have flames whenever I want. Has anyone dealt with this modification before? I'd like big flames, but I really don't like the idea of my engine running wrong and needing work because of it, or even breaking down/blowing up. What do you think?

Also, the Detroit Autorama takes place Feb. 26-28, and I've applied to be in it again. Anyone want to meet up?

HUMVEE Driver

[cruzn2the max]

hi Dave

I have flame throwers on my 49 chev and they work a treat. You can buy a lil electronic box which i bought ages ago for $100, i hooked it up to two
coils which are connected to spark plugs mounted in the rear of the exhaust, i also have a cutoff switch on the distributor to cut the engine for bigger
flames, but i have a choke on the car and use that when doing it.
They are not the easiest to use but i have been practicing it for a few years now with my son and friends copying my setup. I run a 3inch pipe out
the back and in my opinion that size pipe you get the best flames.
There are cars that use gas (LPG) in the exhaust but i have never tried this, however they are getting 20foot flames, but they are cheating as they
are feeding it.
If you want more infomation im more than happy to take more detailed pics to help ya out.
I think these days the kits for this are around $160 $200 but then i havnt looked at what they are worth these days. i got mine off Kustoms of Australia, but i got mine cheaper as i used to work for him at his shows then.
I even had them on my hotrod with exhausts straight up and without a choke they were great.
I also am going to put them on my interceptor down the track just for a bita fun, and because i can...


If you have a strong engine you wont have a problem and you dont have to realy rev it all that much, its just getting the choke in the right position, my
mate actualy put a stopper on the choke and he does better then me, he gets big flames when it is idleing, and consistant.
It also can depend on carby combination to, its all trial and error.

cheers Al

[aussie muscle]

Wow, Crusin, it looks like Max's booby trap!!

[Big Bopper Bart]

Was about to say the same thing lol.Maybe thats what it really was a "flamethrower" kit but hooked up to the tanks instead

[HUMVEE Driver]

Well, I did it, I ordered a flamethrower exhaust kit for the Machine. I had to find some heat-resistant sleeves for the spark plug wires too, as they will be inside the exhaust stacks and they'll melt if they come in contact with the pipes. I might have to work out an on/off switch too.

So, that's the next step! Also this summer, I'm going to be raising the front fenders. Lots of cutting, grinding, and welding involved there.

I'll keep everyone updated! Wish me luck!

-HUMVEE Driver

[mack tanker]

Sounds good
It may get a little warm behind the wheel

[HUMVEE Driver]

If Lord Humungus can take it, so can I!

HUMVEE Driver

[HUMVEE Driver]

Here is my idea for mounting the spark plug inside the exhaust stack. I weld four bolts like that and put four long nuts on the ends. It goes in the pipe and the bolts are tightened against the pipe wall to hold it in place. The spark plug holder nut/bung is welded in the middle. Then I have to drill a hole way down the exhaust where it twists and turns and fish the spark plug wire through. The wire will be insulated by a heat-resistant ceramic sheath. I'm worried about getting a good seal where I drill the hole. Any thoughts on the hole/seal part?





HUMVEE Driver

[the armourer]

I think you are over complicating it, Dave. I'd just machine up a bushing for the spark plug and weld it into the pipe. You can locate it where it's not readily visible. Then there is no need for a fire-resistant sleeve for the wire because it will be outside the pipe. I don't see any way to 100% seal the opening if you tried running everything internally. You will have flame leakage. And eventually you will need to change plugs, so an external mounting will be much easier to deal with then something internal.