turbo exhaust flow dynamics?

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blinker_fluid
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Obviously the exhaust flows front to back but does it also have a spin to it on a turbo car. The reason I'm asking is b/c I'm going to be putting on a morroso spiral flow muffler and wanted to know if it would flow better with the fins pitched one way or another.


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evildky
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it would flow better if you got a straight through muffler, if you must runa baffeled muffler the exhaust would be going into the pipe in a clockwise motion, which that muffler if the pic is acurate would place the fins in a counterclockwise motion, and if you reveresed it itwould be the same, I'd recomend against that muffler

Jerminator96
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evildky wrote:it would flow better if you got a straight through muffler, if you must runa baffeled muffler the exhaust would be going into the pipe in a clockwise motion, which that muffler if the pic is acurate would place the fins in a counterclockwise motion, and if you reveresed it itwould be the same, I'd recomend against that muffler
evildky is right, you're best bet is having no baffles at all. What does morroso give as the reason for arranging their baffles in that way?

crzycav86
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blinker_fluid wrote:Obviously the exhaust flows front to back but does it also have a spin to it on a turbo car. The reason I'm asking is b/c I'm going to be putting on a morroso spiral flow muffler and wanted to know if it would flow better with the fins pitched one way or another.
it might have a spin for about 6 inches, then it will be as turbulent and random as any exhaust. it does not matter which way you have the fins.


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evildky
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the if not for disruption the exhaust will continue to spiral, the most power for a turbo will always be a straight through design, baffels = bad

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95lstegman
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that won't help your exhaust flow, but this will:\________/ ________/~~~~~~\

hard to draw, but i don't have anything to post up a paint pic or something. basically, a venturi, usually at the header collector, and an expansion, properly placed and with a specific taper, can make nice power gains. this requires some engineering to get into the ballpark, and some dyno testing usually to get the best, unless you're a super baller and have access to Riccardo or something ($$$ engine dynamics software, most notably used by Ferrari F1 team).

all exhaust flow on any car is going to have rotation. the velocity and flow rate are both high, the joints in tubes cause more turbulence, and the header and exhaust are strewn with bends. perhaps some sort of stabilizer would help, but you'd almost need one after every bend or joint. too many other things to do that make a bigger difference to bother if you ask me.

neonbomb
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FYI Fluid dynamics is much easier if you think of your fluid (Air) as a saturated liquid (liquid). The rest is pretty much common sense.

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raremotive
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the straight pipe is best... but it is also VERY LOUD!

So best way to reduce noise is to baffle it...that design nearly mimics the effect that turbo reduce exhaust noise. It allows sound waves to cancel each other with minamal restriction unlike other designs...that are much more restrictive... however this design will not be quieter than the more restrictive baffles, but quieter than the straight pipe...

edit:btw... if you have a cat.. then any spin created by the engine/turbo, or any bends before it will be eliminated. So only thing left is the bends, but it's minamal so it doesn't matter if the baffles are clockwise or counter.
Modified by Rare_f8 at 8:57 AM 5/8/2008


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