Exhaust Question - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

anonomousdrift · 03-10-2011, 07:53 PM

Okay so first a little background. Car is a s13, stock ka, has a straight pipe and custom exhaust from a muffler shop that the previous owner put on. I want to replace the exhaust because it sounds terrible and is falling apart and I dont really think its helping any with power. I've already decided on the exhaust I want, but I'm debating on whether to put a cat converter back on the car. I know since the car isn't turboed it needs some back pressure and so heres the question. Do I need the cat back on or will it be okay with a straight pipe? and if it needs the cat, should I put on the stock cat or a high flow cat? Any help would be appreciated.

For those that dont feel like reading everything:

Going to replace exhaust
Stock KA
Has straightpipe
Should I put the cat converter back on for backpressure?
If I put cat back on should it be stock or high flow?

Kemps · 03-10-2011, 08:01 PM

Put the cat back on, you live in Cali, wouldn't wanna get caught up, its not turbo'd and it's a KA.

nismoman · 03-11-2011, 09:53 AM

Exhausts don't need backpressure to work. That is a myth!! You need proper sizing to keep the exhaust velocity up.

HS13KLS · 03-11-2011, 10:40 AM

There was a thread a few years ago.. a blue/silverish hatch who did a dyno on his stock KA.

turns out he made the most power with a buddy club spec 2.

just make it loud and awesome.

anonomousdrift · 03-11-2011, 07:05 PM

Quote:

Originally Posted by HS13KLS

There was a thread a few years ago.. a blue/silverish hatch who did a dyno on his stock KA.

turns out he made the most power with a buddy club spec 2.

just make it loud and awesome.

Was this with the stock cat on?

I'd love to get a spec 2 or Nur spec but Irvine cops love to give out exhaust tickets because they are bored. I'm thinking of getting the tanabe concept g since its supposed to be under the decibel limit.

91cupcake240 · 03-11-2011, 10:52 AM

Blitz nur spec will do the job!

Sent from my T-Mobile G2 using Tapatalk

CaptainVlad · 03-12-2011, 07:09 AM

Whats with everyone thinking Nur Specs are loud... They are not...

mySRblows · 03-12-2011, 01:15 PM

high flow cats = bullshit. for your setup the gains or alleged gains in power wouldnt be worth the cost. ive used a few and honestly i cant tell the difference from stock. it will be fine straight pipes as far as function goes, but from experience i think cat+resonator+muffler sounds the best. ive run muff only, cat/muff, res/muff setups and all of them sound raspy.

EsChassisLove · 03-12-2011, 01:23 PM

Quote:

Originally Posted by mySRblows

high flow cats = bullshit. for your setup the gains or alleged gains in power wouldnt be worth the cost. ive used a few and honestly i cant tell the difference from stock. it will be fine straight pipes as far as function goes, but from experience i think cat+resonator+muffler sounds the best. ive run muff only, cat/muff, res/muff setups and all of them sound raspy.

Honestly the only thing a hi flow does is help spool. But its so minimal you will never notice. I have a Hi flow catco, didnt notice the diff when i put it on and i still pass emissions lmao

anonomousdrift · 03-12-2011, 02:08 PM

Quote:

Originally Posted by CaptainVlad

Whats with everyone thinking Nur Specs are loud... They are not...

I've just heard they are. And everyone I know that has one gets pulled over where I live so I'm just going off that.

Quote:

Originally Posted by mySRblows

high flow cats = bullshit. for your setup the gains or alleged gains in power wouldnt be worth the cost. ive used a few and honestly i cant tell the difference from stock. it will be fine straight pipes as far as function goes, but from experience i think cat+resonator+muffler sounds the best. ive run muff only, cat/muff, res/muff setups and all of them sound raspy.

Thats really what I'm looking for. I dont really want a raspy sound.

Quote:

Originally Posted by EsChassisLove

please put the cat back on. That amount of pollution is not worth the 5whp you gain from it.

Good point. I really don't think 5whp is going to help much on a stock KA

Quote:

Originally Posted by EsChassisLove

Honestly the only thing a hi flow does is help spool. But its so minimal you will never notice. I have a Hi flow catco, didnt notice the diff when i put it on and i still pass emissions lmao

Passing emissions without any problems would be nice. haha

EsChassisLove · 03-12-2011, 01:22 PM

please put the cat back on. That amount of pollution is not worth the 5whp you gain from it.

redline240sx · 03-12-2011, 02:13 PM

Staight pipe is going to be loud, really loud. I had my exhaust with a straight pipe for a year and it was loud and annoying.

Put a catback man...

DirtyLoud · 03-12-2011, 02:40 PM

Put the cat back on. Shit reaks and you can get busted!

03-10-2011, 07:53 PM	#1
anonomousdrift Leaky Injector Join Date: Jul 2009 Location: Irvine, Ca Posts: 65 Trader Rating: (5) Feedback Score: 5 reviews	Exhaust Question Okay so first a little background. Car is a s13, stock ka, has a straight pipe and custom exhaust from a muffler shop that the previous owner put on. I want to replace the exhaust because it sounds terrible and is falling apart and I dont really think its helping any with power. I've already decided on the exhaust I want, but I'm debating on whether to put a cat converter back on the car. I know since the car isn't turboed it needs some back pressure and so heres the question. Do I need the cat back on or will it be okay with a straight pipe? and if it needs the cat, should I put on the stock cat or a high flow cat? Any help would be appreciated. For those that dont feel like reading everything: Going to replace exhaust Stock KA Has straightpipe Should I put the cat converter back on for backpressure? If I put cat back on should it be stock or high flow?

03-11-2011, 09:53 AM	#3
nismoman Zilvia Junkie Join Date: Jul 2005 Location: Bowie, MD Posts: 412 Trader Rating: (0) Feedback Score: 0 reviews	Exhausts don't need backpressure to work. That is a myth!! You need proper sizing to keep the exhaust velocity up. __________________

03-11-2011, 10:52 AM	#6
91cupcake240 Zilvia FREAK! Join Date: Jul 2010 Location: oxnard ca. Age: 36 Posts: 1,084 Trader Rating: (12) Feedback Score: 12 reviews	Blitz nur spec will do the job! Sent from my T-Mobile G2 using Tapatalk __________________ _____________________________

03-12-2011, 01:22 PM	#11
EsChassisLove Nissanaholic! Join Date: Jan 2011 Location: San Diego Age: 36 Posts: 2,090 Trader Rating: (26) Feedback Score: 26 reviews	please put the cat back on. That amount of pollution is not worth the 5whp you gain from it. __________________ IG/TikTok-ThatS14_Z06guy

03-12-2011, 02:13 PM	#12
redline240sx Zilvia Addict Join Date: Jun 2008 Location: Queens, NYC Posts: 706 Trader Rating: (9) Feedback Score: 9 reviews	Staight pipe is going to be loud, really loud. I had my exhaust with a straight pipe for a year and it was loud and annoying. Put a catback man... __________________ 91 S13 Ka-t

03-10-2011, 08:01 PM	#2
Kemps BANNED Join Date: Mar 2011 Location: Orange County Age: 36 Posts: 47 Trader Rating: (0) Feedback Score: 0 reviews	Put the cat back on, you live in Cali, wouldn't wanna get caught up, its not turbo'd and it's a KA.

03-11-2011, 10:40 AM	#4
HS13KLS Zilvia FREAK! Join Date: Aug 2006 Location: Illinois/California Age: 35 Posts: 1,114 Trader Rating: (13) Feedback Score: 13 reviews	There was a thread a few years ago.. a blue/silverish hatch who did a dyno on his stock KA. turns out he made the most power with a buddy club spec 2. just make it loud and awesome.

03-12-2011, 07:09 AM	#7
CaptainVlad Zilvia Junkie Join Date: Oct 2007 Location: Chicago, Illinois Age: 34 Posts: 331 Trader Rating: (4) Feedback Score: 4 reviews	Whats with everyone thinking Nur Specs are loud... They are not...

03-12-2011, 01:15 PM	#8
mySRblows BANNED Join Date: Feb 2011 Location: on the moon bitch Age: 37 Posts: 48 Trader Rating: (1) Feedback Score: 1 reviews	high flow cats = bullshit. for your setup the gains or alleged gains in power wouldnt be worth the cost. ive used a few and honestly i cant tell the difference from stock. it will be fine straight pipes as far as function goes, but from experience i think cat+resonator+muffler sounds the best. ive run muff only, cat/muff, res/muff setups and all of them sound raspy.

03-12-2011, 02:40 PM	#13
DirtyLoud BANNED Join Date: Feb 2011 Location: SoCal Posts: 68 Trader Rating: (2) Feedback Score: 2 reviews	Put the cat back on. Shit reaks and you can get busted!