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Exaustpipe 2

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Irwin

Mechanical
Feb 25, 1999
148
HU
Some years ago I heard about a sport car with a special exaust pipe. After the engine somewhere they installeded an "after burning". They injected in this part addition fuel. Somebody told me this part sucks the engine and we will get better mixture inside engine. Is it true? Does sombody know anything about this system? Can somebody tell me a site where I can see something about this?

Best regards,

Irwin
 
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i think you are referring to Smokey Yunick 's
article a long time ago about injecting "AIR" not fuel into the exhaust ..to increase exhaust temps and reduce emissions

Injecting fuel would waste gasoline and decrease mileage and increase costs, dangerous !!! Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers
 
Honda used to inject water in the exhaust on its two strokes race bikes. It injected at midrange RPMs with full throttle only. It helped to increase midrange power. Maybe this have something to do with the car you are talking about.
Francois
 
World Rally Cars inject fuel into the exhaust before the turbo. The fuel detonates and keeps the turbo spinning; this prevents turbo 'lag' and improves engine response. Maybe this is what you mean. It's certainly not road legal, or even recommended though!
 
AS I remember the last answer is the correct for me! Thank you very much! Can you tell me where I can find something more?

Irwin
 
My question would be "where does the air come from in the exhaust upstream of the turbo?"

Do they inject air as well? Is the engine running very lean at that time for some reason?
 
I saw this system , or something like it, on a factory Porsche CanAm car about 25 or 30 years ago. Apparantly it worked. There is a small amt of o2 in the exhaust I guess. It has been a long time, there might have been an air injector also, I don't remember. Don't see anything like it today, maybe there is good reason?


Rod
 
I didn't reply because I hoped someone would have the definitive answer.

Formula 1 cars used this system. I never thought to ask where the oxygen came from - I hardly imagine that F1 cars are running super-lean!

In motorsport the throttle is either open or closed, and I'd guess that when it is closed the fuel is cut off, so there'd be some oxygen around in the exhaust manifold for the first little bit of a new acceleration, which is where the turbo lag really hurts. Maybe they ran a very lean part throttle mixture, to get round the corners?
Cheers

Greg Locock
 
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