Backfire Effects from exhaust?

  • Thread starter Thread starter WhiteSW20
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...but our VW Passat TDI(110PS!)never "let it brn"!!!
...only the tuned "COSWORTH-FORD ESCORT" (400PS)of a good friend´s(<--R390 Lover) unkle can make such fire coming out of its exhausets but basically u´re right cuz it happens in racecars but racecars are cars too THE ENGINE is only working much harder AND MOST IMPORTANT OF ALL MUCH FASTER(usual car max 6000rp/m and racecar max 10000rp/m!!!)so the PROBABILITY of igniting fuel IN the exhaust is much higher than in usual cars!!!
 
Normal cars have things that prevent unburnt exhaust from firing up. Race cars however, have exhausts that look more like a steel tube. There is nothing that prevents the unburnt exhaust from firing up there, as if they did put something there it would add to the weight and require more maintanance..
 
Yeah the cats (catalytic converters) stop the gas and they are probably the first thing you take off when you race a car out. Just don't expect it to be street legal.
 
lol.......I know......was just wondering..... :rolleyes:

oh and p.s............ure avantar rules.......sooooooo much...it actually looks like Lego people or somthin!!
 
robin2223
lol.......I know......was just wondering..... :rolleyes:

oh and p.s............ure avantar rules.......sooooooo much...it actually looks like Lego people or somthin!!
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Hey thanks, though I can't take credit for it. Found it on a wrx forum.
 
GT-One LoverTHE ENGINE is only working much harder AND MOST IMPORTANT OF ALL [SIZE=4
MUCH FASTER[/SIZE](usual car max 6000rp/m and racecar max 10000rp/m!!!)so the PROBABILITY of igniting fuel IN the exhaust is much higher than in usual cars!!!
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Where do you get your info from it isn't rev's and most race cars don't hit 10000Rpm's they are close to the road cars they are based on in most cases.
 
It all depends on the car. There are some race cars that do rev that high, but there are also alot of low reving pushrod V8 engines in racecars that spit there own share of fire.
 
Yep a car that rev's low can backfire just as much as a car the rev's over 10k, it's all about unburnt fuel getting into the exhaust, and anyway xcsti no one said race cars don't rev that high, but MOST don't.
 
yo......how come flames come out only when you chage gear.....what has the gears got to do with the exsaust......genuine question
 
When you change gear the rev's change rapidly which can cause the fuel to get into the exhaust.
 
GT-One Lover
...but such things we won´t see till GT5(???) unfortunately not :(:(:( 👎 !!!
Toygtone-LS2.jpg



but who knows..............
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Wicked... is that a TS020? :trouble:
 
phantasm
^ ya i remember reading some of your posts... and laughing... i think it's fine as long as you do it with whit and mockery as opposed to saying "hey noob you're an idiot" or something that lacks creativity even more than that statement ;)

I think what aggravates most GTP enthusiasts is that good discussions, intelligent points, and interesting facts about that which they love (GT) are lost with mind-numbing - i hope cadillac is in, gt needs better ai (with no explanation of why they think that), or countless other wishlists rant threads that are created from scratch every day even though the top 3 threads are already discussing these topics.
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Beautifully said man... lolz you a CLOWN :ouch: Niceness
 
Any flame from an exhaust is unburnt fuel, simple as that, unless the car is on fire. The means by which however the unburnt fuel gets into the exhaust can vary.

Most cars impliment a system called "overrun fuel cutoff" which cuts the fuel supply back to an absolute minimum (well under 1% Injector duty usually) when the car is coasting along with the throttle closed, this gives good economy, however without overrun fuel cutoff, the full fuelling can still be delivered into the engine when lifting off. So with the engine coasting it has no need of this high volume of fuel, hence it disappears down the exhaust mostly unburnt and ignites in the hot rear section of the exhaust, especially as it starts to meet fresh oxygen on the way out.

More appropriate to modern cars however is simple rich mapping. High performance Turbocharged engines (Nissans RB series in particular) like a rich mixture (lambda 0.8 or 11.8:1 AFR minimum for any long term durability) when you have this very rich mixture in the combustion chamber it is quite common on lift-off for a little of this rich unburnt mixture to head down the exhaust and ignite in a brief pop, hence why the pops are usually quite a short flash of flame. Cars that sustain a big flame of more than a couple of seconds are "usually" running without overrun fuel cutoff.

Hope this clears up any questions about "why" flames come out of exhausts. This is something I do have a fair bit of experience with. :p
 
...thanx for clearing up 👍 !!!
...but this doesn´t change anything in the point that we ALL want this little little little detail in GT4!!!....it´s not that much work isn´t it?....so let´s hope that GT4 will include this "burning" which we hopefully will see at the racecars(GT-One,R390,F1 GTR,...), at the sportscars(darin favorite SLR---hope it´s in GT4 too:)---,S7,Zonda,Speed 12,...)and perhaps at some tuned cars(Nismo 400R,Celica tunning car,...)

miaooouuuuu i want GT4!!!!!!!
 

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