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Old 07-09-2013, 10:32 AM   #1
ScoobyDrift
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Member#: 315446
Join Date: Apr 2012
Location: Trinidad
Vehicle:
2004 Impreza 2.5L

Default Exhaust size?

Advice, i'm running TWE Stage 2 cams and BC 1600 titanium spring and retainer set. I want like to know what size exhaust to use currently i have 2 1/4'' piping but a number of people told me that its too small i should use 2.5''.

Can anyone advise me accordingly.
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Old 07-09-2013, 01:10 PM   #2
Masta Splint
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Tech. the 1 you have is a good size but you can def go bigger. You can comfortably do a 2.5" exhust and I would not go anything past 3", the 3" may even be a tad bit on the large size since you dont have a turbo.
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Old 07-09-2013, 06:15 PM   #3
GrundleJuice
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Quote:
Originally Posted by ScoobyDrift View Post
Advice, i'm running TWE Stage 2 cams and BC 1600 titanium spring and retainer set. I want like to know what size exhaust to use currently i have 2 1/4'' piping but a number of people told me that its too small i should use 2.5''.

Can anyone advise me accordingly.
What header is or will be installed? Match the collector size is usually a sound choice.
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Old 07-09-2013, 06:23 PM   #4
ScoobyDrift
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I'm running brolas unequal headers
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Old 07-09-2013, 06:35 PM   #5
EdHilario
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As long as it's a true 2 1/4" diameter piping and mandrel bends, it should be enough. Do you have a catalytic convertor? If so, that's a restriction right there. If you have to do emission tests then leave it on. Otherwise you can replace it with some piping.
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