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Discussion Starter #1
if i make a 2.5 inch exhaust flex back, while im n/a will i lose power. i plan on going turbo in the future but i dont know when.
 

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[FJ] Special Ed.
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maybe you should hold off on fabbing the exhuast if your not going to have the turbo to supply it.. why lose power when you can just wait?
 

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im not looking for all the power in the world or anything but i really just want the sound. i would like some more hp. i dont race my car or anything.
 

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if you have more than basic bolt ons, then a 2.5" exhaust will be fine. I've seen a 2.25" and 2.5" exhaust dynoed on another Zetec powered car with bolt ons, SCT chip, and cams and the 2.5" exhaust made more power than the 2.25" exhaust from 3000 RPM and up.
 

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Discussion Starter #6
currently i dont have any mods but ohh well i might just do it
 

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if you have more than basic bolt ons, then a 2.5" exhaust will be fine. I've seen a 2.25" and 2.5" exhaust dynoed on another Zetec powered car with bolt ons, SCT chip, and cams and the 2.5" exhaust made more power than the 2.25" exhaust from 3000 RPM and up.



Thank you. Putting on a 2.5" exhaust won't cause you to lose power, it will move the power to a higher point in the rev band.
I tested this thoery a couple of years back and you have less tq off the line, but catch up quickly. In the end, you are sitting at the same spot as the car with a 2.25" exhaust.
So realistically, you don't lose, but you don't gain either. Everything is just shifted. People who tell you anything else are just guessing. I hate when people do that around here.
 

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GoatRoper's ride is NA and he has a 3" system. Doesn't look like he is losing any power... LOL.
 

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I'm getting ready to fab a new exhaust for my ZX3. It'll be 2.25" from the flex back into a Camaro style(crossflow) muffler which is 2.5" then it'll be dual 2.5" out the back.(which will only be like 2 ft. of pipe out of the muffler). I will also be installing a JBA shorty header this weekend.

-Mike
 

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You Can't Make Me Laugh
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I kind of debunked that theory a bit.
Huh?


I've got a NA ZX3 with a Kamikazee header (w/2.5 collector) with a 2.5 flex, going to a 2.4 (60mm) Apexi and my low, mid, and high RPM's pull just fine.
 

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Hes trying to say he debunked the theory of "big pipes reduce power" BS. Hes got, OMG 3 INCHES!!! And has no signs of being weak... So your on the same side.
 

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Huh?


I've got a NA ZX3 with a Kamikazee header (w/2.5 collector) with a 2.5 flex, going to a 2.4 (60mm) Apexi and my low, mid, and high RPM's pull just fine.


[/QUOTE]

I agree with Kona here. Well, in a way, I used to have a SVT header/RT cat/FS flex/FS exhaust but since I am going to get the Roush kit soon, I got rid of the header and found an Apexi for cheap. Now, I have my stock header and cat with the FS flex and Apexi. This thing pulls. Sometimes it feels like I have my header on. I wish I would've found the exhaust before I took off my header. But, a 2.5 does not kill your horsepower/torque in anyway.
 
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