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Discussion Starter #1
can any one explain/define pro's / cons of the following set up
3" intake, 3" DP, 2.5" catback exhaust.

I have a lead on a good deal for magnaflow system for the sedan, but it is 2.5" piping. I intended on getting 3" intake and DP, but am concerned about performance robbing by using a smaller size exhaust. Is there any reason for concern or should I just with 2.5"?

Any input you can provide is greatly appreciated.

-Steve
 

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I'm not a mechanic or an engineer. As far as 2.5" vs 3", there wont be much noticeable loss w/ a 2.5" if staying within a certain HP. 3" intake also wont benefit. I'm not 100% sure about the stock size, but I believe it's less than 70mm (which is less than 3"). If youre not planning to swap turbos or anything like that, a larger intake pipe may end up hurting more than benefiting, till you get it pro-tuned.
What are your goals?
 

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IMO - A 2.5" exhaust is good to about 350hp, (3" is good to about 600hp) so it really depends on where you want to end up. If you think that you are going to swap turbos and go stage 3 then you might want to think about a 3" CBE. Other than that there really is no huge advantage intalling a CBE that is larger than the one needed to support the mods that you are running.
 

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I'm not a mechanic or an engineer. As far as 2.5" vs 3", there wont be much noticeable loss w/ a 2.5" if staying within a certain HP. 3" intake also wont benefit. I'm not 100% sure about the stock size, but I believe it's less than 70mm (which is less than 3"). If youre not planning to swap turbos or anything like that, a larger intake pipe may end up hurting more than benefiting, till you get it pro-tuned.
What are your goals?
^^^^ That is good... I just read your post... OEM piping is small tapers down to 1.75" - 1.5"
 

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Discussion Starter #5
I'm not a mechanic or an engineer. As far as 2.5" vs 3", there wont be much noticeable loss w/ a 2.5" if staying within a certain HP. 3" intake also wont benefit. I'm not 100% sure about the stock size, but I believe it's less than 70mm (which is less than 3"). If youre not planning to swap turbos or anything like that, a larger intake pipe may end up hurting more than benefiting, till you get it pro-tuned.
What are your goals?
Actually I did intend to go stage 3, but would be somewhere in the 350 hp or less. I was thinking something like the AVO 380 turbo or similar. This car is my daily driver, but I like to go to the drag strip and do participate in auto-x. My plan was to do larger CAI, FMIC, Turbo swap, DP and exhaust along with necessary supporting mods. I've already got the clutch upgrade to handle the add'l power. I was going to the whole stage 3 at once, but as I mentioned, I have found a deal on the exhaust and I only want to buy once, and a deal just makes it that much better. Do you think the 2.5" will be ok or should I go with the 3" set up?

thanks again for your input.
-Steve
 
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