Its usually caused by massive overfuelling! Everyone thinks its cool because old rally cars did it but they actually did it on purpose to keep the turbo spinning (anti-lag). If our car was spitting flames we would be having a word with our tuner!

 

Unburt fuel in the exhaust, most of the time its perfectly normal and harmless.

 

That depends on your point of view of course! If you are running a cat it will destroy it eventually and do you really want to pay to throw fuel down the exhaust?

 

I suppose certain tuners map the cars to fuel slightly differently to others, so it really depends what software you are running?

 

I wonder what the turbo temp is under a spirited drive normally

 

What AFR does tigger run Andy?
There's nothing wrong with it spitting some flames, better to fuel on the rich side than run it lean. I just see the remark of 'having a word with the tuner if it spits flames' as a little bit flippant.

 

It runs at 12 all the way to the redline. I was just saying that if our car suddenly started spitting flames, which it never has done, i would think there was something wrong with it! A good example is that when the MR2 was running a MAF sensor based fuelling system and an atmospheric dump valve it used to spit flames and generally run like a bag of poo, once we reworked the DV to make it recirc it stopped flaming and ran a million times better!

 

It's certainly a neat party trick of the focus though

 

Spirited driving =hot turbo/hot exhaust - throw fuel into that and youl get a flame.

When spirited driving you let off the throttle quick to change gear, and so the throttle butterfly snaps shut, you then have a richer mixture in the cylinders and so it gets pushed out into the hot turbo/exhaust and youl get a flame, it's split second stuff and you can even get a wee flame from a standard RS if its being driven hard!

It is pretty normal!

 

Wee flames are but some of the ones ive seen look like a Cozzie with a flamer kit off of the 80s lol!

 

That's not really what you said though Andy

you said 'if our car was spitting flames' not 'if it suddenly' totally changes the meaning. Also in pretty much the same thread on STOC you inclined the same kind of thing, that the mapping was out

 

In my opinion if a cars spitting huge flames theres a problem with the fuelling. I cant see why that would upset anyone? It is after all my opinion and i havent said that any map or mapping company is rubbish, unlike a lot of posts i see?

 

Ive had some pretty impressive ones with standard mapping, full mongoose exhaust and mountune airbox.

Just roll the boost on and back off for a couple of seconds in 6th. Cossie style stuff

haha!

 

I only ever get flames on full acceleration gear changes, but i do get pops and little bangs on the overrun. I just assumed the flames were due to the fact you have gone from full boost (lots of air) to very little in a split second and the engine continues to inject some full, running a bit rich. The unburnt fuel then mixes with air in the hot exhaust and ignites. Wether this is on purpose to keep the cylinders/head cool or because the fuel system lags a bit i dunno.

Wasn't the RS engine designed to pop and crackle on the overrun anyway? i imagine fitting a free flowing exhaust/decat would magnify it. I have heard of atmospheric dump valves producing a lot more flames because the air they dump was metered for combustion and the engine runs rich for a short time after the valve dumps.

 

Nothing wrong with a few good flames. I love em, one of the best features. I had a corker in 6th gear last Saturday night. My misus thought it was a speed camera flash but it must of stayed alight for 2 seconds

 

Cant see the attraction in them myself, i'm glad my cars quiet, refined & doesn't spit flames!

 

Same with ours! We often get comments at trackdays saying how good it is to see a car thats so quick but doesnt sound like a night out in Beirut! Its also great not having to worry about noise tests as it only makes 89db lol!

 

There have been a lot of catalytic converters trashed as well. Great having the pops and bangs if that's what you want, but like everything, it comes with a price I suppose.

 

Just take your cats out and spit as many

flames as possible lol, that is itself a show for other cars following our RS in a tunnel !!

 

+1 Nicely said!!

 

Do you get flames regardless of sports cat/de cat?

 

Excessive over fuelling / running rich can be as bad s running lean for an engine. Both will lead to trouble.

Occasional flames are fine, if its flaming excessively I'd be concerned

 

Products of combustion like carbon monoxide will self ignite at 560 degrees with no source of ignition

 

That makes sense. On my scan gauge, my cat was reading over 600C after a bit of a drive.

 

These are the biggest I've seen:

https://www.youtube....h?v=FONn7TnLewo

 

I get flames I'm running a stage 1 map - KMS full De-cat system - J1 air filter

Get huge flames when its HOT!!!

 

Where is the stage 1 map from?

 

I suppose the hotter it is the bigger they will get?

 

Flames!!! If that happened round here, the way some people sit right up my rear, I'd melt their front grill!

 

other than over fueling you can get a kit which sprays a tiny ammount of fuel into where the lamba sensor would be on a de-cat and you get a nice bang and flame on gear changes above 4000rpm.

cant remember where this kit has gone though was a Japanese company but they only made it for the GTR34

 

Im running a revo stage 4 with a sport cat and as far as I know I get in flames.... lots of pops and bangs tho... I think if I was to decat maybe then I would get some...

 

i get a few nice ones, only put the decat on the other week. somtimes it will flame constantly and other times i cant make it happen for love nor money

 

how do you guys see your own flames lol?