Is a 3" exhaust to big for a N/A engine?

fritz

Well-Known Member
457
322
atlantic city, nj
Vehicle Model
civic si
Body Style
coupe
I want to order an exhaust asap for my si, but I am not sure what to go with. I would like to see some kind of power gains and not just a diffrence in sound. I was considering full race 3" but a friend said that is too big for a N/A engine and wont help in any power gains. Any thoughts?
also do I need to include the a down pipe to get any real gains with an exahust?
:feedback:
 
There is still quite a bit of debate about 2.5" vs 3", but more importantly you will need FlashPro to really take advantage of any potential gains. A downpipe would help a lot too as you would be getting rid of one, if not both, of the cats.
 
I just picked up flash pro the other day (Highly recommended for anyone thinking about it) and I want to do some kind of exhaust before I get her tuned from vitviper. With all the choices it can be a little daunting trying to make a choice.
:banghead:
 
I really want to do an exhaust, too. Other than no money to spend on one right now, I am waiting to see if anybody puts out a full system.
 
I put a full race cat back and I love it. The sound is incredible and the throttle feels much more responsive. There is a huge difference not only in sound but in performance from the tsudo 70mm (i could never get it to stop leaking) to the full race. I plan on tuning but as of right now just to much money to tune.
 
there is a thread somewhere... ill try and find it... but they found that the 3" made power through the entire rpm range which surprised everyone. These engines seem to like the large exhaust quite a bit and getting the 3" definitely leaves the option open for FI later on. The full race is also a really really nice system anyway.
 
3" exhausts are great for 2006-2011 Si's. I'm sure it's the same for the 2012+, but Vitviper did mention that the gain is not as significant.
 
3"+ EXHAUST IS STRONGLY SUGGESTED FOR FORCED INDUCTION VEHICLES. THERE WONT BE ENOUGH BACK PRESSURE AND IT'LL SOUND PRETTY SH*TY IMO. THE RPMS WILL BE HELLA HIGH BUT YOUR CAR WILL LOOK LIKE YOU'RE GOING SLOWER THAN WHAT THE RPMS SHOW. :spinning:
 
3"+ EXHAUST IS STRONGLY SUGGESTED FOR FORCED INDUCTION VEHICLES. THERE WONT BE ENOUGH BACK PRESSURE AND IT'LL SOUND PRETTY SH*TY IMO. THE RPMS WILL BE HELLA HIGH BUT YOUR CAR WILL LOOK LIKE YOU'RE GOING SLOWER THAN WHAT THE RPMS SHOW. :spinning:
Strongly suggested for FI applications? Why do most NA 2006+ Si owners have 3" exhausts on their cars?
 
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3"+ EXHAUST IS STRONGLY SUGGESTED FOR FORCED INDUCTION VEHICLES. THERE WONT BE ENOUGH BACK PRESSURE AND IT'LL SOUND PRETTY SH*TY IMO. THE RPMS WILL BE HELLA HIGH BUT YOUR CAR WILL LOOK LIKE YOU'RE GOING SLOWER THAN WHAT THE RPMS SHOW. :spinning:

I don't quite understand your post.....

Won't be enough back pressure for what? Have you listened to any of the sound clips of the full race 3" exhaust? Sound is subjective but it is really nice sounding.

Also, why would putting on a 3" exhaust raise your rpms? Look like you're going slower?

YOU'VE ALSO OBVIOUSLY HIT THE CRUISE CONTROL BUTTON FOR COOL.
 
It's like saying that a 3.5" intake is NOT RECOMMENDED FOR NON-FI CIVICS!!!
 
DOES IT LOOK LIKE I EVEN KNOW WHAT I'M TALKING ABOUT, CLEARLY A NEW MEMBER! SMH. LOL. I KNOW NOTHING ABOUT CIVICS, SORRY.
 
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I TEND TO BE A SMART *** SOMETIMES AND ACT LIKE I KNOW EVERYTHING. MOST OF THE TIME I REPEAT WHAT I HEAR FROM OTHERS..
 
Well I guess be decent, act like your age, stop the caps lock, and we'll help you out. :thumb:
 
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