Are exhaust pops a sign of power

obi_waynne

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Do you think that exhaust pops when you lift off are a sign of power?

Many drivers think so but don't appreciate what causes it or what effect it has on engine performance and catalyst life.

What do you know about exhaust POP's - share your knowledge and thoughts here and hopefully we can dispel a few myths or maybe even confirm them.
 

thexav

Pro Tuner
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387
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2002 Clio 172
AFAIK these are caused by unburnt fuel igniting in the exhaust. It will kill a catalyst.

The engine is running too rich or the exhaust ports are opening too soon which will sap power as the flame front exits through the exhaust port rather than pushing the piston fully down.
 

T9 man

TC ModFather
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Saab 9-3SS T9
Not sure about the above explanation there ?-/
I was watching a video on You Tube the other day of the old school Audi Quattro giving it the full beans on a rally stage, it was popping and banging all over the place, yet still spanked everyone on the circuit :)
 

wizzer

Road Burner
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Lyndhurst, Hampshire
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VW Golf 2.0 TDi
I like to see cars spitting flames, but only when they do this for real, people with those silly flamer kits should be banned.

Highly tuned engines will spit out flames, there is usually no catalyst to worry about. I thought the popping noise was due to the turbo spooling up and clattering as air rushes the wrong way over the turbines when you lift off.
 

obi_waynne

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Deal, Kent UK
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A3 1.4 TFSI 150 COD
Afaik they use a Spark plug in the exhaust trail pipe. Some run the engine rich others spray fuel into the exhaust then they use the Spark plug to ignite it.
 

T9 man

TC ModFather
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From
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Saab 9-3SS T9
Afaik they use a Spark plug in the exhaust trail pipe. Some run the engine rich others spray fuel into the exhaust then they use the Spark plug to ignite it.
Ruddy frightening o_O

I remember once popping along to a place in Grays Essex to get something done to the Beast in the early stages of it's evolution and saw this kit. I thought to myself - WHAT! :eek:
Sorry but flames coming out of the rear end of a car should be contained to the Batmobile only.
 

TCJBOLDIE

Torque King
Points
667
From
Brisbane
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JB Starion
Not sure about the above explanation there ?-/
I was watching a video on You Tube the other day of the old school Audi Quattro giving it the full beans on a rally stage, it was popping and banging all over the place, yet still spanked everyone on the circuit :)
Os it was the anti lag working to keep the turbo shaft speed high on a closed throttle. It is hard on turbos though.

http://www.rallycars.com/Cars/bangbang.html
 
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