flames from exhaust?

[fuzzy]

what causes this ? after a race today with my mate in his type r he says that flames were popping from my exhaust at high speeds after high boost when changing gear. is the cause of this something that needs attention sooner rather than later or is it something that doesnt matter. it does look cool from behind though he says

[tylerma]

I think its something you can expect from certain turbo applications mate

[munky30]

Own up, its you flamer kit really... you think its wikid koool innit.

[lenny-d]

Own up, its you flamer kit really... you think its wikid koool innit.

[Demlotcrew]

Mines pops all the time

Dont worry mate the only damage could be to the exhaust. (baffles)

But otherwise its very very cool!

Andrew

[1an]

you will normally get flames from the exhaust if you have more of a straight through pipe due to the combustion in the engine etc, but it definatly looks and sounds good.

[nzracer]

popping flames is uber

flamer kits are so

[zaust]

Hey m8.. Unburnt fuel hitting atmos at high speed. Dark orange flame, normal on cozzy lumps over 320 bh.

[zaust]

I say find yourself a twin pleninth and run 8x grey's, some bd10 cam's 12 bar actuvator and a breather for the head..

[Onz]

flames ROCK!!!

[Turbo-Brown]

Only reason you'd be getting popping and flames when you lift the throttle to change gear/decellerate is a mega lean light load mixture which passes through the engine and then ignites in the exhaust.

Probably nothing to worry about although it shouldn't really do it if the tuning's right.

[CUTZ]

dont really matter i had that on my honda civic vti its becoz of the exhaust

[Jesus325iTouring]

Used to look super cool on this twin piped Mark 1 RX7 Concept car I used to drive.

I was also lead to believe it's unburt fuel igniting in the exhaust.

[snoops]

what causes this ? after a race today with my mate in his type r he says that flames were popping from my exhaust at high speeds after high boost when changing gear. is the cause of this something that needs attention sooner rather than later or is it something that doesnt matter. it does look cool from behind though he says

who won?

[Car-Nut]

I heard it was the same as "JESUS"

My Evo 6 used to do it through a 4 " blitz exhaust when I was younger

[Turbo-Brown]

It is unburned fuel catching fire in the exhaust, however the unburned fuel ends up in the exhaust as a result of a lean mixture on the over-run.

You can either get around the problem by having an over-run fuel cutoff (although anyone who's driven a 205GTi will tell you the cutoff's a deeply unpleasant thing to have to live with) or having a mixture that's not going too much over 18:1 on the light loads.

It's one of those things where you can have nothing and it's fine, or just the right amount and it's fine, but somewhere inbetween's a problem.

[munky30]

Whats it mean when a car pops and bangs but there's no flames?

When I let off the gas and let the engine brake, my car pops and bangs, afaik there's no flames and I know I dont have a turbo...

[Jon_Bmw]

Have you got an atmospheric dump valve?

[Theo]

Munky, does you bodgemobile have a badly blowing exhaust?

[munky30]

No, my bodge mobile has a 3" 'straight through HKS backbox on a standard front and middle section.

(It was free and got me through my mot before anyone starts)

[Theo]

A straight-through backbox? Surely that would simply be a pipe!

[munky30]

pretty much... you can see all the way through it but it does have some stuff around the outside... not much though.

[Jesus325iTouring]

Hmm,interesting,on my old 325 (I had when I was young and foolish) I put twin straight through Cherry Bomb silencers on,these were of the literal sence staight through,loud as f uck but no pop and banging on engine braking etc

[Turbo-Brown]

Whats it mean when a car pops and bangs but there's no flames?

When I let off the gas and let the engine brake, my car pops and bangs, afaik there's no flames and I know I dont have a turbo...

It means it's running lean on the over-run. It makes no difference whether there's a turbo, supercharger or whatever, when the throttle's closed, you don't get boost whatever type of FI you run.

It's exactly the same for NA too, a lean mixture causes popping and / or flames when the throttle's shut and the revs are highish.

[munky30]

Is it doing any damage?

I kinda like it... but if its not a good thing I'd rather do without it.

[Turbo-Brown]

Probably not, there's not enough air passing through the engine for it to generate much heat.

Have seen someone's exploded silencer though, caused by a fuel buildup in the box which ignited with an almighty bang.

[JazzMan]

A straight-through backbox? Surely that would simply be a pipe!

This is what magnaflows straight through boxes look like on the inside:


http://www.magnaflow.com/wideopen/wideopen.asp

They are quite loud! But they do small ones and big ones so you can put complimentary smaller mufflers in somewhere in the system if it's too loud

[glenbat]

Same as Zaust says Fuzzy, unburnt fuel being dumped into atmosphere (via exhaust) and igniting.. Higher powered cossies often do it with no source of ignition, and the last few yrs have seen every other turbo'd car have a flamer kit (a spark plug drilled into their exhaust and a switch on dash) fitted to look coooooooooooooooooool
My old saph used to do it quite a lot too (no flamer) usually on gear changes, I THINK as you back off the throttle a small amount of fuel is dumped and this tends to go up

[CraigG]

on vauxhall 16v engines, fuel is used to cool the piston crowns on over run, ie, it injects fuel with no spark, this then gets into the exhaust next cycle. afaik its fairly standard practice for turbo'd cars aswell, as the engine temps are much higher.

nothing to worry about tbh mate.

[tailoutcharlie]

both my mk2 golf gtis did that, assumed it was just something they all did.

used to think it made my car sound like a 'rally' car!

[lenny-d]

just get some anti lag launched on there and do it propperly

wwwwwwwaaaaaaaaaaaaammmmmmmmmmppp bang crack fart bang wwwwwwwwwwwaaaaaaaaaaaaaammmp

[nickso]

apologies for the awful picture taken from a vid i cant get to work but this is my mates rsturbo which shoots 6 foot flames out the back, there is no flamer kit.

[tailoutcharlie]

jesus!

bet he doesn't have probs with people sitting on his bumper.

[curryp]

that must be over fueling or somthing.thats unreal and must do some sort of damage if not to the car,then to whoever is stood near! nice mobile bbq for this time of year though

[Simon]

My M3 does it too, and have witnessed it myself, when the missus was driving it!!