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exhaust ?? 2.5" pipe??

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ok, i might have found a shop that might fab me an entire exhaust system, told them i was thinkin a bout 2.5" pipe from the turbo to the tailpipe.. guy told me they'd have to see if they could use the flanges on my pipe, which they are all good except the one goin to the turbo, which i have a spare downpipe anywho...

 

my question is can it be done :confused: any recommendations:confused: should i put a cat on it or not:confused: should i get the crossover pipe fabbed also while i'm at it:confused: should i go 2.5" or 2":confused:

 

you all prolly know i needed the midpipe anyways, but my welds on the downpipe broke again, so its time this hole damn thing goes.. gettin tired of messin with it.... my appointment is friday so ya'll got a couple days to gimme some feedback on this. thanks..:-p

I'm looking at doing the same thing soon

 

Steve is running 2.5 inch from the turbo back.. looks much cleaner without that stupid stock downpipe. He kept his legal with a 3 way cat about halfway back.. does the job of the 2 cat setup that the soob has stock.. even the cat is 2.5 in and out.. sounds cool. wan't very expensive either if I recall

  • Author

no muffler? just the 2.5" to a 3way cat, then pipe out the back?

 

that sounds about what i wanna do... wheres the O2 sensor go in a custom downpipe?

forgot to add that there is indeed a muffler there.. not sure what kind.. it is also 2.5 in and out I believe.. I never thought to ask about the os sensor.. good quesion

mines a junkyard downpipe someone had already had made up and added the 3way cat to it

its definetly larger than the stock downpipe

i am running straight exhaust no muff..

sounds very cool

just have a few joint leaks under the car to solve

but is relativly decent on the inside at 55mph not very loud

2.5" is perfect for our car. It's what I'm going with. Here's the general rule of thumb for displacement and exhaust pipe sizes for turbo motors.

 

1.0-1.4L - 2.0"

1.5-1.9L - 2.5"

2.0-3.0L - 3.0"

 

For full race systems go .5" bigger.

I used a Jegs high flow three way - only

2.5 " turbo back

maybe a little far from the engine

will find out next emiss. inspect

Sounds nice and quiet untill I open the tailgate.

completesyst.jpg

2.5" from the turbo back with 3 way catalytic converter, all the way out to the rear. Series 40 Flowmaster. Nice mellow, deep noise until you step on the loud pedal. Definate power gain from stock, yeah, definately, yeah, yeah, definately. 81 toothpicks.

 

 

In my opinion, I think I'm getting more gain out of the bigger exhaust than the FM, it's just there for noise.

 

Regards,

Jay

the turbo out is esentially 2.5 from the O2 sensor back... when things "Calm down" and I can spend time with Ed out at his barn then the turbo adapter plate will have the O2 sensor nipple and EGT nipple welded to its neck... And so you already know, the 3-way cat is actually in the place of the original 2nd cat from its OEM days.

 

The muffler is a 2.5 in and out as well.... some off brand of the turbosonic design its a striaght thru style but truthfully - we tested it in the muffler shop with stratpipe and then with the muffler installed. the only difference was at speed the muffler takes "the edge off the sounds" and allows a Very quiet ride.

 

The Smog test was very productive too. I was quite happy with it.

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