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Discussion Starter #1
Hi all,

Could anyone explain what was the exact purpose of the special device on this periode made ' racy' Sprint exhaust ?
It seems that at the ultimate pipes, external frech air was added and mixed with the exhaust gasses .
Just guessing:
  • Was it done to lower the CO2-emission ???
  • Was it an attempt to increase the speed of the exhaust gas flow ?
The incomplete brand label mentions ' a press.... ', could mean something like 'pressurized' ?
I would choose the second reason but, being no specialist in this matter, I would certainly value your opinions !


Rgds,

Thierry

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It might have been done to dilute blue smoke. GM transit buses had a venturi sucking fresh air in the exhaust pipe to dilute the black soot from the diesel emissions. This was in the day of the 2 stroke Detroit Diesels and was kept up to the appearance of diesel particulate filters.
 

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Hi all,

Could anyone explain what was the exact purpose of the special device on this periode made ' racy' Sprint exhaust ?
It seems that at the ultimate pipes, external frech air was added and mixed with the exhaust gasses .
Just guessing:
  • Was it done to lower the CO2-emission ???
  • Was it an attempt to increase the speed of the exhaust gas flow ?
The incomplete brand label mentions ' a press.... ', could mean something like 'pressurized' ?
I would choose the second reason but, being no specialist in this matter, I would certainly value your opinions !


Rgds,

Thierry

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Introduce fresh air at the exhaust tip will turn it into a flamethrower when the hot exhaust with some unburned hydrocarbons ignite.
 

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Discussion Starter #6
Hi Yves & all,

From CARSPECTOR, an automotive dictionary on the Net, I found these definitions of a 'thermal reactor':

" [1] A high-volume thermally isolated chamber replacing the exhaust manifold and providing a place for high-temperature afterburning of exhaust pollutants. Found on all Mazda rotary engines and some piston engines (BMW for example) as well.
[2] A device installed in the exhaust manifold of some air injection systems to promote HC and CO oxidation by providing long exhaust gas residence times in a localized area.
[3] An emission control device that accepts raw exhaust gases from the engine and subjects them to extremely hi temperature to oxidize noxious emissions. Uses a specially designed exhaust manifold that uses heat and air to burn the unburned hydrocarbons in the exhaust gases to reduce pollution. "


On this particular Giulietta exhaust, I don't see where the extra heat would have come from, and the air was entered only at the very end of the ultimate pipes .

Rgds,

Thierry
 

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Introducing air (with oxygen) into the exhaust stream will cause a backfire at the exhaust tip. This is especially true on a rich overrun condition (like when you let off the throttle after a high speed run.) Doing this induced a high vacuum in the intake manifold. And the carburetor sensing this higher vacuum dumps fuel from the idle port into the air stream. Since this extra fuel is not needed, it passes directly into the hot exhaust. Once it reaches the exhaust tip, with the additional air/oxygen, it burns (backfire).

So what you have here is a gimmick. To create this backfire condition.

Reed
 

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When I referred to a thermal reactor, I was just kidding. It is the same general idea, but in a totally uncontrolled manner.

I can't find anything on this brand "SAMAP" or "SAMAR"...
 

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Discussion Starter #9
Thanks Yves, this has restored my trust in you .:geek:
Btw, I looked for S.A.M.A.F but couldn't find it either.
Rgds,

Thierry
 
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