Forced Induction Discussion of turbos , superchargers , and nitrous upgrades on the G35

For a turbo setup, 3" exhaust or a true dual 2.5" exhaust?

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Old Nov 4, 2012 | 12:06 AM
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For a turbo setup, 3" exhaust or a true dual 2.5" exhaust?

What works best for maximum gains?
 
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Old Nov 5, 2012 | 10:12 PM
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Are you referring to a 3" single vs a 2.5" dual? The dual will allow more air flow.
 

Last edited by herrschaft; Nov 5, 2012 at 10:30 PM.
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Old Nov 7, 2012 | 04:09 PM
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I had a 3" dual but it was painfully loud so I swiched back to a dual 2.5" and I am not sure if I lost power but I dont even care the car is so much nicer to drive now.
 
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Old Nov 8, 2012 | 03:07 PM
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I see dual 2.5" it is!
 
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Old Nov 8, 2012 | 03:09 PM
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Originally Posted by herrschaft
Are you referring to a 3" single vs a 2.5" dual? The dual will allow more air flow.
Crazy, i'd imagine not much could out perform a 3" single setup
 
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Old Nov 8, 2012 | 03:19 PM
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Originally Posted by JaE35
Crazy, i'd imagine not much could out perform a 3" single setup
A 3" dual
A 3" single would work great on a single turbo setup. If there's 1 turbo per bank though, then theoretically a 2.5" dual should permit more air flow then just one 3" pipe. I'm not a tuner but to me that makes sense.
 

Last edited by herrschaft; Nov 8, 2012 at 03:38 PM.
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Old Nov 8, 2012 | 03:21 PM
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2.5" TD will be just fine up to 500whp or so.
 
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Old Nov 22, 2012 | 10:52 PM
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Originally Posted by seymore4
2.5" TD will be just fine up to 500whp or so.
Or 625whp
 
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Old Nov 23, 2012 | 06:22 PM
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Even going to 2.75 asks a big commitment- the noise is a lot more of an issue by a long shot. I went with 3" down pipes too... Which don't help.

I'm really, really hovering on switching those back out for my 2.5s... It really just makes the car so much more relaxing to drive yet with most if not all (at my level) of the power available.

If I did the heads and got bigger turbos- okay- now the 3s make sense... But not at this point.
 
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Old Nov 29, 2012 | 09:39 PM
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Two 2.5" pipes will flow about 36% more than a single 3" pipe, given that we are referring to nominal OD with a .063" wall thickness and ignoring skin friction losses.
 
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Old Dec 15, 2012 | 11:08 PM
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The bigger the pipes the faster the spool. And more power. Turbos needs as much airflow as possible

I got dual 3"s

It's not that
Our, the turbo cuts a lot of the sound out with the right free flowing mufflers. My car is quieter than half of the na vq's
 
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Old Dec 15, 2012 | 11:12 PM
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^what exhaust homie, I can only find 2.5 dual, hell all the hks' i see are smaller than that. I like the Ark grip but it is only 2.5
 
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Old Dec 16, 2012 | 01:01 AM
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Originally Posted by ITNKICN
Even going to 2.75 asks a big commitment- the noise is a lot more of an issue by a long shot. I went with 3" down pipes too... Which don't help.

I'm really, really hovering on switching those back out for my 2.5s... It really just makes the car so much more relaxing to drive yet with most if not all (at my level) of the power available.

If I did the heads and got bigger turbos- okay- now the 3s make sense... But not at this point.
Had my car for the past 3 days which is also 3" downpipes and the Greddy Ti-C dual. It was extremely loud and droned like crazy at first. But, I just installed the silencers tonight that came with the exhaust and those made a tremendous difference, probably about 50% quieter. My previous HKS dual(2.25") was louder then what I have now.

Install the silencers and you'll see the difference
 
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Old Dec 16, 2012 | 05:24 AM
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Getting the pricing for the AAM Competition 3 in. True Dual Exhaust (Titanium). Time to let the twins breathe!
 
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Old Dec 18, 2012 | 10:14 PM
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With open dumps you should be fine with 2.5
 
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