Car exhaust spouting flame

[661-Pete]

(video to follow).

On a small, noisy sports car that overtook me this morning. I've seen such things happening on dragsters, but not on a public road. I think I have useable footage but I shan't know until this evening.

Should I report this to the police? I'm minded to do so as soon as I've checked the video.

[edit] video added:
[youtube]hBYxSCAK5yg[/youtube]

[honesty]

yes. its probably an illegal mod to dump fuel into the exhaust to ignite. I'd report them. I'd be surprised anything happens, but that's a different story.

[661-Pete]

Illegal - yes, must be! Quite aside from the fire hazard, or the risk of serious burns to a cyclist or pedestrian right behind the vehicle, the pollutant emissions must be off the scale.

[honesty]

The only other way to get flame is to run a really rich mix so that so much fuel is being used un-burnt fuel is getting into the exhaust from the engine. You have to remove the catalytic converter for this to work as well, so illegal on a road car...

[greyingbeard]

perhaps tell the dvla if the police arent interested

[Brucey]

it is probably a boy-racer mod.... but it is also possible it is a 'standard feature' on some cars if the car has a sports mode which is really meant for track use or something.

Cynically, if that part of the duty cycle isn't tested during standard emissions tests, it doesn't 'need' to comply.... ....and by comparison with recent revelations concerning emissions tests that would be small beer.

Is there a good reason (or at least an excuse) for overfuelling between gears? Well who knows... but for example car manufacturers will throw fuel down the exhaust pipe to heat the catalytic converter up more quickly (even on shopping cars), and on rally cars at one time they often had an additional injector between the cylinder head and the turbo; this allowed fuel to be burnt there on the overrun and this kept the turbo spinning between gears. Since most road cars now have turbos, and have clever management systems, maybe they do the same thing on those now; probably it doesn't even require an additional injector, it might just need a 'fuel with no spark' condition between gears. An aftermarket chip may accentuate this feature too.

Is it dangerous? Probably. But then tonne lumps of metal flying around anywhere near flesh and blood is never going to be 100% safe either, sadly....

cheers

[Audax67]

VW or Audi?

[recumbentpanda]

Batmobile.

[Audax67]

VW Batmobile or Audi Batmobile?

[old_windbag]

I think there are a number of "supercars" that do naturally run flame on the overun. I think this is simply the way the engine management is configured, on top gear they had a lamborghini that visually threw out blue flame on one of their grand tours through alpine tunnels etc. It was more visual at night. I hear many highly tuned motorcycle engines crackling and popping... sometimes a full backfire, again this must be the state of tune throwing unburnt fuel out. As another poster states this may involve not having a "cat" as the unburnt fuel would cause damage. There are many tuned up hot hatches that wish to emulate this phenomena . Perhaps they inject fuel after the "cat" on souped up cars for pure effect. The link below has a good mix of standard performance cars and souped up saloons and hot hatches..... don't mouth off to a driver when behind one of these, you may find your bullet cam badly singed .

https://youtu.be/_4-pL7hbQdc

Modern diesels with particulate filters I believe burn fuel in the DPF to clear it, the lack of regeneration leading to the DPF light issues that many complain about. This wouldn't cause a flame-out though but may help prevent the huge black cloud that envelops you when a diesel driver "boots it". I also read about unburnt fuel being passed through high performance petrol engines to cool exhaust valves( I think that was in motorcycle news ), I think that was the purpose. One of my cars had sodium cooled exhaust valves, be good to saw them in two and throw in bucket of water .

[mig]

might help dry my bl**dy boots out....

[661-Pete]

I've added my video to the OP. Seems to be a Toyota (can anyone confirm?). Time to have a try at Operation Crackdown I think.

[old_windbag]

Its a toyota mr2. In a nice shade of fyffes yellow. They are good cars actually must be well tuned up.

[661-Pete]

Thanks for info. If it was 'well tuned up' it wouldn't be wasting fuel on 'batmobile' stunts...
I've sent the info in to the Plod. See if they are interested.

[Ray]

Ah, the MR2! Didn't that model have to change its name for the French market? Or is that apocryphal?

"Oui, monsieur, c'est vraiment MR2."