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Turbo flash. Fire out the tail pipe?

Aside from modifying your car to be a “flamethrower” (spark systems in the exhaust to light unburned fuel) is there any type of turbo/supercharger/mod that will cause fire to vent the entire length of the exhaust system?

Not if everything is working properly!

As a matter of fact, if everything is working properly there won’t be enough unburned hydrocarbons in the exhaust to make flames. Not even close. It would need an additional fuel supply being sprayed into the exhaust stream with a source of ignition. And a really good health insurance policy.

I’m still trying to figure out if the OP wants to achieve an adolescent light-show effect, or if he has a malfunctioning car that he is trying to cure. I really hope that it is the latter, but in either case, your advice regarding good health insurance (or life insurance!) is definitely valid.

well, if they had an older vehicle, pre-catalytic converter, he wouldn’t need that extra fuel source. I remember an episode of Pimp my ride that was doing a 66 Mustang and the guys wanted to put one of those flame thrower kits on it, but that idea got nixed.

I think I saw that segment.

I’ve seen TV segments of cars with the flame thrower kits installed, but I’ve never seen one using only the exhaust to make the flames without added fuel.

I was wondering about the flashes of flame you see on nascar when they are going into the turns.

Not 20foot flames, I am wondering about something like this:

(not the last part, just the popping of flames, such like they get on nascar when going into a turn)

We used to do this all the time back in high school (and even managed to blow apart a few mufflers). All one had to do was simply turn off the key for 5-10 seconds while going down the road. This caused the exhaust system to fill up with unburned air/fuel. When the key got turned back on - kaboom!

I never tried it on a car with a catalytic converter. The cat would not like the unburned fuel.

Now with fuel injected cars, turning the key off turns the fuel off as well.

My favorite place to do this was on the I15 (Wilbur Cross) Parkway Tunnel. The tunnel helped to amplify the sound.

NASCAR and drag racers don’t have to worry about pollution controls. The fuel mix for max power can have unburned gas in the exhaust. The exhaust systems are straight pipes, not CATs, no mufflers, and shorter pipes. All contribute to a more dramatic flames out of the exhaust.

There’s a guy around town with a seriously old hot rod with a flame thrower installed. He apparently has a fuel source injecting fuel into the exhaust pipes and a spark source to light it.

We’re a little town, and we used to have some pretty comical parades around Christmas and the 4th of July, which included tractor trailers, dump trucks and hot rods. This guy was in a few of those parades, and going really slow, or even stopped he’d rev the engine and light his flame thrower. Lots of flames out the back, but on more than one occasion he had to get out and put out the fire on the street.

In the really bad old (carbureted) days, all it took was a spark plug in the tail pipe. Thre was usually enough unburned fuel (especially if you ran the carb rich) that a spark plug near the tip of the exhaust would produce flames.

My question to the OP is . . . why? Rocketman

I’m trying to figure out if it is a side affect of a hot car, or an add on. In a lot of movies you see things like this. Just wondering if it is fictional.

At least in my state, you don’t have any controls on your exhaust on all cars over 25 years old. Someone drives a tubbed out 50 something f1 pickup with a massive spoiler and wheely bars around my city on sunny days.
Will a hot engine shoot a flash down the pipe or not.

EVERYTHING you see in the movies is fictional…

For a really good flame it’s an add-on.

A buddy hand an old 50’s Ford he did it to. He stuck an HEI distributor in the trunk with a blower motor to spin it then welded some spark plug bungs into the tailpipes and wired it all up. Sometimes he could get a nice flame by putting on the choke while driving down the street, other times he would shut off the engine and pump the gas a bit.

I believe the NASCAR bit is from raw fuel burning off in the pipes as they let off the gas, perhaps the engine is a bit lean on the overrun? I know my motorcycle pops like crazy on the overrun; people say it’s from a lean condition even though it makes little sense to me.

Don’t use NASCAR as an illustration that a stock engine can blow flames out the tailpipe. As previously metioned, NASCAR vehicles are pouring a lot more fuel in without regard to unburned hydrocarbons, and they’re engines are turning much faster (valves almost “floating”), their ports are much bigger and their valves staying open longer per stroke (allowing a coomparatively almost unrestricted huge path into and out of the cylinders), their cylinders are running hotter (no need to worry about NOx or preignition) and they’ve little in the way of the exiting exhaust. In short, the fuel is still not finished burning as it’s blown rapidly past the exhaust valves. Their valve timing is probably totally different than yours too, but you get the idea.

Their brakes are cool to see too. They use special ceramic discs that glow bright yellow when they get hot…very, very hot.

For raw fuel to be burning off the engine would have to be rich on the overrun. And that makes sense. They go from pouring fuel in with the throttle open (air passage less restricted) in a very open passage (with recognition of the restrictor plates NASCAR requires, the ports etc are pretty well open) to suddenly retricting the air intake with the throttle. Even though lateral wall pressure at the orafice pulling in fuel is above the throttle plate and the sudden decrease in velocity should increase lateral wall pressure and the fuel drawn in should drop off, perhaps the fuel pressures they run at allow a rich amount to enter the venturi even under throttle-closed conditions.

Or perhaps something they do with their ignition timing is a factor.

I don’t know how they run those engines, but exactly why the fuel is there in the exhaust stream making the flames is an interesting technical problem to ponder.

I agree! Use NHRA instead!

They make those special for Columbia or someplace in south america I believe. Since kidnapping is quite common, people have been known to attach flame throwers to their vehicles to prevent this