exhaust - benefit of dual out over single out
#1
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I was discussing with someone the benefits of dual in/dual out exhaust on a 911 as opposed to the factory dual in/single out. This is while using heat exchangers or headers. My friend wanted to know the increase in horsepower of dual out from single out, but I couldn't find my Bruce Anderson book to prove my argument.
Can someone post the horsepower differences between dual in/dual out and dual in/single out?
TIA
Can someone post the horsepower differences between dual in/dual out and dual in/single out?
TIA
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#2
RL Technical Advisor
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Hi:
Good question!
This really depends upon the the design of each muffler in question as every manufacturer configures their internals differently. No two are identical. I would further tell you that using a dual-outlet muffler is a bigger factor with a 3.8 litre engine than a 3.0-3.4 one and camshafts play a big role here.
I can tell you that in the case of the Monty mufflers, there is very little difference in power (maybe 3-4) between their single outlet version vs. the dual outlet versions. Its mostly a sound change and of course, cosmetics.
Good question!
This really depends upon the the design of each muffler in question as every manufacturer configures their internals differently. No two are identical. I would further tell you that using a dual-outlet muffler is a bigger factor with a 3.8 litre engine than a 3.0-3.4 one and camshafts play a big role here.
I can tell you that in the case of the Monty mufflers, there is very little difference in power (maybe 3-4) between their single outlet version vs. the dual outlet versions. Its mostly a sound change and of course, cosmetics.
#4
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ok
from dyno tests on a 3.2 10.8:1 Solex cams, Weber 46
Factory stock muffler..........272hp
Super trap (95db discs)........275hp
Borla..........................277hp
Triad single w/crossover.......279hp
Factory sport (two in two out).279hp
Triad dual out track muffler...285hp
Megaphones.....................289hp
couldnt find any real world numbers on the monty
from dyno tests on a 3.2 10.8:1 Solex cams, Weber 46
Factory stock muffler..........272hp
Super trap (95db discs)........275hp
Borla..........................277hp
Triad single w/crossover.......279hp
Factory sport (two in two out).279hp
Triad dual out track muffler...285hp
Megaphones.....................289hp
couldnt find any real world numbers on the monty
#5
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ok
from dyno tests on a 3.2 10.8:1 Solex cams, Weber 46
Factory stock muffler..........272hp
Super trap (95db discs)........275hp
Borla..........................277hp
Triad single w/crossover.......279hp
Factory sport (two in two out).279hp
Triad dual out track muffler...285hp
Megaphones.....................289hp
Question: where in the powerband would most of the increase come on the Triad?
Anyone know how much the Triad is?
Does anyone have any photos of the Triad mounted on their car?
TIA
from dyno tests on a 3.2 10.8:1 Solex cams, Weber 46
Factory stock muffler..........272hp
Super trap (95db discs)........275hp
Borla..........................277hp
Triad single w/crossover.......279hp
Factory sport (two in two out).279hp
Triad dual out track muffler...285hp
Megaphones.....................289hp
Question: where in the powerband would most of the increase come on the Triad?
Anyone know how much the Triad is?
Does anyone have any photos of the Triad mounted on their car?
TIA
#6
Rennlist Member
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d230:
Here is a link to their website. I know one guy who has one on his 2.4 with MFI. Their site says they custom build them.
<a href="http://www.triadwestperformance.com/Products.htm" target="_blank">http://www.triadwestperformance.com/Products.htm</a>
Here is a link to their website. I know one guy who has one on his 2.4 with MFI. Their site says they custom build them.
<a href="http://www.triadwestperformance.com/Products.htm" target="_blank">http://www.triadwestperformance.com/Products.htm</a>