293 posts
1991 240sx fastback, 2000 maxima se
toms river nj
2-19-2007
turbo exhaust flow dynamics?
9:01 AM 3/5/2008
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 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
"if I had all the money I ever spent on cars........I'd spend it all on cars" 12.378 in a rusty datsun with a sliping clutch "The Rusty Mistress" 299.3 whp and 305 lbft TQ, 2105 lbs I'm cleaning out my garage, lots fo Z parts, S30, Z31 and Z32 here is my ebay listing http://motors.search.ebay.com/_W0QQsassZevildky if you're looking for something shoot me an e-mail, evildky@bellsouth.net
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?
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.
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.
~Jason, PayPal Verified (20), also on honda-tech.com with the same user name. Sport: '89 Nissan 570SX - 325RWHP/320rwtq, >300ft*lb 1500-5500rpm <2600lb DD: '05 RSX w/ Leather; '94 Toyota Corolla DX (beater)
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.