Building Custom Catback, Best Exhaust Piping Size?

[p75dsm]

Hi guys and girls, i have a N/T Eclipse and will be upgrading exhaust(for real this time) right now all it has is an AEM short ram intake and a welded cheap n1 ebay muffler on stock exhaust pipe. I will be buying either a 4-2-1 or 4-1 header, POSSIBLY AEM Cold Air Intake, have a Tsudo N1 muffler i will have welded on at the up and out angle the apexi or hks has and will reroute the exhaust piping under the rear cross member to be able to do this. Ive been searching and searching about n/t dsms aswell as other n/t cars and have found minimal info but what im wanting to know is what will be best pipping size?? possibly from N/T owners who have either size piping.. i know full catback systems come with 2.5 piping but from what im hearing it might be best to do 2.25 piping(which i think is the stock size pipe) but i dont want to lose the little power i do have..i want improvement.

 

[bagged420a]

If your staying n/a go with 2.5". You won't be changing anything going to 2.25" as I believe that is stock? You want it to breath more, so go with the larger 2.5"

 

[p75dsm]

have been contemplating going turbo and still might and if i did it wouldnt be for another year or 2 but i think i just want to get it the way i want until i can afford to buy a gst/gsx/tsi.

im leaning toward 2.5

anyone else??

 

[805DSM]

2.5 for sure

 

[p75dsm]

i did a search at autozone and their replacement muffler for the n/t eclipse has a 2 inch inlet...anyone that knows what the stock size is for the rs/gs?

 

[Beemer92]

If you gonna stay relativly stock turbo or not, then 2.5 inch would be the max I would use. You could try 3 inch, but you risk losing power due to little to no velocity of the exhaust gasses. Bigger is NOT always better.

 

[p75dsm]

no no im not even considering going 3 inch unless i was running a decent amount of boost. 2.5 is the most i was thinking anyway but im wondering if theres any power loss in going to 2.5 over the stock 2.25

 

[gringo72884]

I've had a n/a 1g which I eventually converted to turbo....from experience the best size would be 2.5 inches...any bigger u will lose torque....any smaller and you wont see or feel any noticeable gains...

 

[805DSM]

i did a search at autozone and their replacement muffler for the n/t eclipse has a 2 inch inlet...anyone that knows what the stock size is for the rs/gs?

if your going for the "sleeper" route, id go with a 2.5inch magnaflow muffler and just paint it black and add a small stock looking tips on it. pepboys stocks them

 

[bagged420a]

but im wondering if theres any power loss in going to 2.5 over the stock 2.25

There will not be power loss in going 2.5". It will net power, especially if you upgrade to headers and cai.

 

[NeMiZiS]

I'm running a full Tsudo 3" exhaust on my N/A.
I didn't really notice much difference.
But it probably is hurting more than helping until it gets turbo'd.
Who wants to buy exhaust twice any way?..

 

[adamtsi]

I'd go 2.5 you may lose a smidge of torque but you'll gain a little up top. But in all honesty I don't think you'll notice any difference in power, mostly just sound.

 

[p75dsm]

yeah for you NeMiZiS it was smart to do the 3" and get that over with since your going turbo..and i thank you for your replies on my other thread about the tsudo..as you can tell from this post i bought a tsudo and cant wait to install it!!

and to 805DSM im not going for sleeper with the exhaust..the autozone stock muffler comment i made was just trying to find out what the stock pipe size was. I actually have a tsudo N1 im building this catback with...well i guess im going with 2.5 piping..the worse that can happen is i wont like it and im out a hundred or so dollars it will cost to make..

so will the 2.5 piping make it louder as in raspy?? cause i DONT want that..