My exhaust is 2.5 inch piping leading to my magnaflow muffler which has a 4 inch outlet. i loved it at first but it felt like i lost power off the line or backpressure i guess its called. so being as broke as i am i opted for the silencer (not to mention the tickets for a loud exhaust) which seemed to tone it down and give back some of the back pressure. well recently it was stolen off my exhaust and i cant help but laugh at what kind of ghetto person would steal a used exhaust silencer. my question is, is it my imagination or am i really slower off the line? is my muffler tip too big? what should i do?

 

Do you have the stock CAT ? header?

 

Yes, i did my exhaust just after the cat and never changed out the headers.

 

With a 2.5" exhaust, don't expect getting off the line anytime soon.

Bigger exhaust > loss of low-end > make up top-end.

 

yeah what u feel is less torque at first and second but u gain some hp after third...now u need to bring more fuel in so it makes up for that air u r now moving

 

^ What Blitz said, but tune up!

 

im all ears on how i can go about this lol :d

 

lol on fuel? easy...fuel pump...fuel rail...fuel regulator(make a return system)....injectors and piggy if u have the $ for it...also breath more...header...CAI for basics...and that well tuned u should be around 180 whp only if u do it well...also UDP that helps a lot 2...

 

2.5 is really only good if your boosting.

 

Too big. Prolly losing torque from our experience.

ROAD/RACE

 

the 2.5 inch piping is too big or the 4 inch outlet? thinking maybe just to get a smaller muffler. the noise after a while on long trips is a headache not to mention its like if donuts had sounds that would be it cause cops love me

 

If you go big, you tune up.

You don't, your loss!

 

i understand, im just trying to learn i never really got into cars till i moved out on my own and got my 02 oz rally like 4 years ago and all i did was cosmetic. now im getting more into engine mods and speed im trying to learn basically on my own, i dont want to admit how little i actually know its embarassing lol, but gotta start some where right? so atm while im extremly strapt for cash im just looking for a fix on my exhaust issue it seems like im burning gas like crazy too since i lost the silencer cause it basically made my muffler a 2 inch vice 4 and im assuming now the car is working harder to do the same job?

 

its 2.25 you want for an NA setup. the problem is not so much about the outlet but the piping itself. do an intake and pulley if you havent yet. then the piggy so you can get more fuel in their to make up more all this airflow.

 

if you don't plan on boosting i'd suggest downgrading to 2.25... 2.5 is definitely killing your low end tq. You might be able to compensate by getting the RRM SRI or some sort of Short piped intake setup... That might bring some lower end tq back in.. As for the gas not sure.. less backpressure might cause that?