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How u doin pplz.
Ive just been wondering why some racing cars have flame comming out of the tip of the exhaust.
I know a bit about why that happens, (a rich fuel and air mixture, and something about the valvetiming) but dont know exactly what takes place.
WHAT exactly happens that causes the flame to be seen at the end of the exhaust tube. :confused:
Flames come out of the exhaust if you run it on pure nos. It can ruin the engine though.
[QUOTE=bballmikey105]Flames come out of the exhaust if you run it on pure nos. It can ruin the engine though.[/QUOTE]
I hope you're not serious about this reply...
im not completely sure, but I know that some ppl (not race cars...;)) burn gas outta their exhaust directly.... :)
all it is is the burn process isn't complete when the gases suppose to be exhausted (i don't even know if thats a really word hahaha). any way thats the reason why you see the flame at the end of the exhaust. all cars do it a bit, but most cars aren't moving enough fuel through for the burn to last long enough to be seen at the end of the exhaust. i hope thats what it is :o :D
Basicly the flames come out when your car does give the engine to much fuel and it cant burn all in the engine and when it comes out of the exhauste the "cold" air makes it's density to grow and it ignites from the heat of your engine exhaust.
Bytw you can make the flames come out on older or newercars(more difficult) by cuting the spark of for an milli second.
But it does it on Need For Speed Underground (Which is such a cool l33t megaa game) so it must be true you don't know anything my Dodge Neon on it goes mega fast with the flames out of the exhaust so ur wrong sahhaaaa
:D :p LOL its true if you use nos there comes flmaes out of the exhaust because of the fact that Nitrous oxide is made up of 2 parts nitrogen and one part oxygen. During the combustion process in an engine, at about 572 degrees F, nitrous breaks down and releases oxygen. This extra oxygen creates additional power by allowing more fuel to be burned. and this means that you will se flames from the exhaust because your car will pump more fuel and som will not ingnite in the engine. (i think this was why i hope im right and not showelling BS) :confused:
Like rally cars, they do it a lot! The 6R4 used to do it a lot to *sniff* before it was put up for sale *weeps uncontrolably* i loved that car.
rally cars do it because of their ALS (anti-lag system) which basicaly dumps fuel into the turbine which ignites, expands and spins the turbo to eliminate lag. the fuel is still burning as it comes out the exhaust
well the V8 Supercars quite often are shown with flames coming out of the exhaust pipe, but i always used to put it down to the engines using street 98 octane petrol rather than a special race blend. after reading most of the replies here im having to reconsider my reasoning
[QUOTE=megotmea7]rally cars do it because of their ALS (anti-lag system) which basicaly dumps fuel into the turbine which ignites, expands and spins the turbo to eliminate lag. the fuel is still burning as it comes out the exhaust[/QUOTE]
megotmea7 is right...
[URL=http://www.rallycars.com/Cars/bangbang.html]Check out this LINK[/URL]
[QUOTE=Need4Speed]How u doin pplz.
Ive just been wondering why some racing cars have flame comming out of the tip of the exhaust.
I know a bit about why that happens, (a rich fuel and air mixture, and something about the valvetiming) but dont know exactly what takes place.
WHAT exactly happens that causes the flame to be seen at the end of the exhaust tube. :confused:[/QUOTE]
1. Well if your a ricer ;) , then you probably have a "flamethrower" (which they used on the cars in 2f2f)
2. If you are using a high compression engine what low octain fuel, it could misfire.
3. if you are using "Top Fuel" (nitromethane) in your engine, then the combustion is still occuring after the exhaust cycle, and out of the tail pipes. (I really really really dought this is the case ;) )
Sorry if I repated someone elses reason, I have not read any responces yet
My ten cents worth. I beleive it to be no more than the combustion of unburnt fuel being ignited by extremeley hot exhaust pipes. In racing cars the pipes are fairly short so when rich mixture is dumped in during decelleration, it reaches the air fairly quickly and ignites due to the heat. The proximity of the tip to the extractor system will also play a part in making the tips unusually hot. Matra, how did I do?
[QUOTE=crisis] The proximity of the tip to the extractor system will also play a part in making the tips unusually hot. Matra, how did I do?[/QUOTE]
For non-cat cars and normal fuels the flame at tip is more to do with the oxygen available.
Not a lot of air in the pipe :) so it won't burn.
It's true that shorter pipes mean hotter gas and more likely to self-combust on meeting air.
Local trade show had a new 'must have' for the boy racers:)
it was an injector into the tail pipe and a spark generator.
Screw it into the last couple of inches of the pipe, plumb the fuel to it, and wire it to a switch. Press the switch and it squirts a small amout of fuel and ignites it to get "realistic flames" from the exhaust :)
Kids in baseball caps all seemed to have one clutched in their hands !!!
you mean flames like this ..... :p
There are two reasons why this could happen, one is the ecu and the car itself is old which could lead to mistakes in the valve timing, the exhaust cycle starts before the combustion cycle is over and the hot gasses created during the combustion process shoot out the back of the muffler
The other reason is that the car is installed with an anti lag system which lowers turbo lag. When a driver lifts off the throttle on a turbocharged car the turbo is still spinning pumping more and more air into the intercooler, the blow off valve then opens to release all this pressure or else the compressed air will shoot back the other way stalling the turbo. when this happens the turbo's slows down since there is less exhaust gas to spool it up. when the driver accelerates again he will experience huge lag since the turbo will have to wait till it gets back to its original speed. Rally cars cant afford to have this type of handicap expecially since they are fitted with an air restrictor. Instead when the driver lifts off the throttle during cornering the valves are opened early and combustion of the fuel/air mixture keeps the turbo spinning. This system although extremely effective is very damaging for the turbo exhaust manafold and the engine itself, that is why they are not outfitted on street cars, well along with the fact they are so loud you will be charged with disturbing the peace.
[QUOTE=stratos]you mean flames like this ..... :p[/QUOTE]
yep just like those flames :p ...
No turbo, short exhaust and I dont think they have cats.
ok i didnt read the whole thread but if this has allready been said ime sorry ok the v8 supercars u go on about is becouse there running straight through exhaust running at the temps they run it ignights the unburnt fule witch comes out of any engine if the exhaust had a cat it couldent do this becouse a cat burns all the fule to lower the hydrocarbon lvls
[QUOTE=bballmikey105]Flames come out of the exhaust if you run it on pure nos. It can ruin the engine though.[/QUOTE] :confused:
i hope ur not serious about that if u ran pure NOS u would blow up th engine
it actually comes from when the gas does not burn completely in the cylinder and is still burning when it comes out of the exhaust
[QUOTE=nrcafootball68]:confused:
i hope ur not serious about that if u ran pure NOS u would blow up th engine
it actually comes from when the gas does not burn completely in the cylinder and is still burning when it comes out of the exhaust[/QUOTE]
ok first off this thread was closed like a month ago ...
2nd you CANT run an engine on NOS, its not combustable
and yes the misfires are caused by either a valve opening too early or unburned fuel igniting in the exhaust, neither of these things is normal and if it happens in your vehicle take it to a mechanic for maintenance as soon as possible
Did you guys see the movie 2 fast 2 furious? If you did, remember that seen were 4 cars are racing down the street at night and each car has a flame coming out of the tail pipe the same color as the cars paint? Any ideas how they did that?
Taz.
this thread was closed a week ago,lol. btw......ya wouldn't think they made the flames out of the exhaust through computers while the cars were goin at 20-25mph?:) like the first movie. + you can always put those flamethrowers in the back like in an episode of "pimp my ride" where they put'em at the exhaust tips of an old mustang.
[QUOTE=taz_rocks_miami]Did you guys see the movie 2 fast 2 furious? If you did, remember that seen were 4 cars are racing down the street at night and each car has a flame coming out of the tail pipe the same color as the cars paint? Any ideas how they did that?
Taz.[/QUOTE]
George Lucas.
[QUOTE=nrcafootball68]:confused:
i hope ur not serious about that if u ran pure NOS u would blow up th engine
it actually comes from when the gas does not burn completely in the cylinder and is still burning when it comes out of the exhaust[/QUOTE]
Nitrous oxide is an Oxidizer. You wouldn't "blow up the engine" if you ran it pure, because it can't burn by itself. You would just spray something completely useless into the combustion chambers.
Do a little research before you misinform people while trying to correct them...
flames often appear when racing cars downchange. The engine is running fast, whereas the throttle is actually closed (just after the obligatory downchange blip when racing), this means cylinders won't be filled optimally. It takes more time to burn the smaller amount of mixture and when the exhaust valve is open the mixture is still burning. Of course a hot exhaust exacerbates all this glorious infernal mayhem! If we were all driving open exhausts we'd hear popping every time we lift off the throttle, using the engine as a brake.
I tried to put the flames down to ignition timing, although I cannot see when it would ignite too late, as ignitions are equipped with vacuum retardation (is this the correct term?) and centrifugal weights.
If someone has a better suggestion, please tell us.
I was registered at your forum. I have printed the test message. Do not delete, please.
[quote=pretygirl;899056]I was registered at your forum. I have printed the test message. Do not delete, please.[/quote]
Delete the white text spam? Oh, sorry.
Usually when you drive your car normally you won't notice, but when accelerating quickly, or breaking suddenly, your car can be adding too much fuel to your engine. Which will get into your exhaust system, in small amounts. From here on it's the process of combustion in your exhaust, for example C8H18 + O2 --AE--> CO2 + H2O. The activation energy that is required is the heat in your exhaust. This reaction is exothermic, mean in releases energy. In form of heat, a Hydrocarbon under the effects of enough energy can cause it to catch fire. Which is what you'll see at the end of your exhaust tip.
[quote=Need4Speed;43812]How u doin pplz.
Ive just been wondering why some racing cars have flame comming out of the tip of the exhaust.
I know a bit about why that happens, (a rich fuel and air mixture, and something about the valvetiming) but dont know exactly what takes place.
WHAT exactly happens that causes the flame to be seen at the end of the exhaust tube. :confused:[/quote]
Obviously because the fuel air mixture didn't burn completely in the cylinder.
As to why can be too many things.
Usually a too rich mixture. Remember race/performance cars are about getting the most power from a given engine size.
Also a too rich mixture can prevent knock somewhat.
Most car that spits massive flames were built with turbo to avoid turbo lags. [url="https://en.wikipedia.org/wiki/Antilag_system"]Antilag system - Wikipedia[/url]