I plan on turbo charging / supercharging my 2004 cavalier and i know i want 2.5" full exhaust for the forced induction and i was woundering how the 2.5" system would do w/o the forced induction b/c i dont have an exact date of when i would get the induction or should i just wait and do it all at once? thanks for any input

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from what other people have said, its gonna suck. at least at the low end. your gonna lose a little power

The 2.5" pipe would hinder performance becuase it will reduce backpressure and scavenging will work less efficiently. If you're going to turbo in a year or two, I'd wait to install the exhaust. You can't really touch the exhaust manifold because replacing that would be a waste of money. If you really want to get something done then replace your cat and the cat-back (that is if you're planning on using a cat), other than that I'd wait until you were closer to the install date.



Blown.

please take backpressure out of your vocab, no matter what backpressure is bad. the major effect in going from 2.25 to 2.5 is the reduce in exhaust VELOCITY. See, you have the same amount of exhaust gasses flowing through a larger crossectional area hence lower velocity. no matter what backpressure hinders performance. the 2.25in pipe is the perfect size for N/A applications because it reduces backpressure from stock, but greatly increases the exhaust velocity, the increased velocity is what enhances the scavenging effect.


Ill make a sig someday

BLAH BLAH BLAH BLAH BLAH !!!! Backpresure, whatever ! I'm running a Pacesetter
4 into 1 header and a 2 1/2 inch highflow exhaust and all I know is if I lost anything at all in low RPM it wasn't enough to make a damn bit of difference. My 60foot times at the track NEVER changed but my MPH in the 1/4 picked up by 1 or 2 and it knocked a few tenths off my times as well. I did 2 1/2 for the same reason I planning for the supercharger and rather then do it two times I did it so it can support any of my future mods. And 2 1/4 just wouldn't cut it for what I'm building.

2 1/2 is fine get it and have fun.




Semper Fi SAINT. May you rest in peace.

Depends on which one, in my opinion. If you are going to go turbo, there is no point in doing this now because when you do your setup you'll be tossing the header and replumbing it anyway.

you should go with a 3" exhaust when you put the turbo in. the air will be going fast enough as is.

Yeah if you do go turbo then you just wasted the cash for the header and down pipe.
Only go this route if your gonna superchage.




Semper Fi SAINT. May you rest in peace.