S14 test pipe

[Anubis]

I want to do something with my catalytic converter, but i'm not sure. I have 2 questions, can an S13 test pipe fit in the S14? and if so, I heard that the S14 will have some type of ECU error because of the sensors placed in the cat? Also, would getting a high-flow cat be better performance wise? &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/huh.gif" border="0" valign="absmiddle" alt=':huh:'>

[tnord]

question #1; why do you specifically want to do something to the cat?
point #1; modifications to the cat result in minimal gains, and more often than not, losses.

[Anubis]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (tnord @ June 30 2002,9:16)</td></tr><tr><td id="QUOTE">question #1; why do you specifically want to do something to the cat?</td></tr></table><span id='postcolor'>
umm to increase power by lowering restrictions placed on the exhaust flow.. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/confused.gif" border="0" valign="absmiddle" alt='???'>

[rotaryknight]

From what I remember the lower cat on the S14 is hollow to begin with. &nbsp;The main cat is the one closer to the motor.

[tnord]

don't expect to gain more than 2hp from doing this. i highly doubt you'll notice a difference. the cat isn't as restrictive as you might think. there are much better places to start modifying than the cat. and if you keep the cat you'll pass emissions (sp?) anywhere you live, and keep myself along with the EPA happy.

if you absolutely must, just get a cat from random tech.

[nismo270r]

If you're going to do anything down there, I'd suggest going with a Hotshot header...which is a full length header. It eliminates the factory cat...the real one that is, right on the end of the factory headers. Then get a Random Tech, or Carsound high flow cat, which would go in the place of your "fake" cat. Can't remember, but I think either one or both of the high flow cats have the O2 sensor bung for the factory O2 sensor that goes in the original cat...Not quite sure why Nissan did this, but I've heard it was to make the car pass visual emissions testing easier...

[rotaryknight]

On a NA car removing the cat doesn't do much anyways like tnord said. &nbsp;On a turbo'd car it does make a big difference though. On the FD removing the main cat can see a 20-15hp gain but then that is on a FD.

[Anubis]

according to the 240SX technical manual, the cat thing after the headers is some type of resonator, and the one under the car is the actual cat. so the hotshot header replaces the entire manifold plus the pipe that connects to the cat?

[nismo270r]

Weird...yah...I just looked at my parts sheets for the S14, and it lists it as you explained it...I've always heard the one where a cat would normally be is the fake one...maybe it's the other way around...Well, either way...A Hotshot header and a high flow cat will do away with them both! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=''>

[Grant]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (anubis9228 @ July 01 2002,10:22)</td></tr><tr><td id="QUOTE">according to the 240SX technical manual, the cat thing after the headers is some type of resonator, and the one under the car is the actual cat. so the hotshot header replaces the entire manifold plus the pipe that connects to the cat?</td></tr></table><span id='postcolor'>
the one under the car is the fake cat.

gains are marginal, usually not worth money spent.

[Anubis]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Grant @ July 01 2002,02:36)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (anubis9228 @ July 01 2002,10:22)</td></tr><tr><td id="QUOTE">according to the 240SX technical manual, the cat thing after the headers is some type of resonator, and the one under the car is the actual cat. so the hotshot header replaces the entire manifold plus the pipe that connects to the cat?</td></tr></table><span id='postcolor'>
the one under the car is the fake cat.

gains are marginal, usually not worth money spent.</td></tr></table><span id='postcolor'>


The nissan tech manual states number 5 is indeed the conveter. But if you don't think they know what their talking about, don't let me hold you back. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sigh.gif" border="0" valign="absmiddle" alt=''>

[Grant]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (anubis9228 @ July 02 2002,12:37)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Grant @ July 01 2002,02:36)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (anubis9228 @ July 01 2002,10:22)</td></tr><tr><td id="QUOTE">according to the 240SX technical manual, the cat thing after the headers is some type of resonator, and the one under the car is the actual cat. so the hotshot header replaces the entire manifold plus the pipe that connects to the cat?</td></tr></table><span id='postcolor'>
the one under the car is the fake cat.

gains are marginal, usually not worth money spent.</td></tr></table><span id='postcolor'>


The nissan tech manual states number 5 is indeed the conveter. But if you don't think they know what their talking about, don't let me hold you back. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sigh.gif" border="0" valign="absmiddle" alt=''></td></tr></table><span id='postcolor'>
there were two cats on the s13s. number 5 is one of them.. on S14, number 5 is hollow.

so basically if you want hotshot headers and still want to pass smog, then go ahead and get a cat, otherwise i dont see the benefits.

[TheTimanator]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Grant @ July 02 2002,03:13)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (anubis9228 @ July 02 2002,12:37)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Grant @ July 01 2002,02:36)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (anubis9228 @ July 01 2002,10:22)</td></tr><tr><td id="QUOTE">according to the 240SX technical manual, the cat thing after the headers is some type of resonator, and the one under the car is the actual cat. so the hotshot header replaces the entire manifold plus the pipe that connects to the cat?</td></tr></table><span id='postcolor'>
the one under the car is the fake cat.

gains are marginal, usually not worth money spent.</td></tr></table><span id='postcolor'>


The nissan tech manual states number 5 is indeed the conveter. But if you don't think they know what their talking about, don't let me hold you back. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sigh.gif" border="0" valign="absmiddle" alt=''></td></tr></table><span id='postcolor'>
there were two cats on the s13s. number 5 is one of them.. on S14, number 5 is hollow.

so basically if you want hotshot headers and still want to pass smog, then go ahead and get a cat, otherwise i dont see the benefits.</td></tr></table><span id='postcolor'>
If this is true than a catback exhaust for the S14 would only be the rear section. &nbsp;Or at least thats what it looks like. &nbsp;Plus the second cat (#6) looks like its welded in according to the picture. &nbsp;and if #6 was the real cat, and a cat-back exhaust went form #5 wouldn't it be illegal b/c #5 is hollow? &nbsp;This is really wierd.

Disclaimer: I don't know much about S14's

[Anubis]

ya, this picture is kinda confusing, im pretty sure number 6 is a sound resonator, and according to people who have done the hotshot header install, all emissions correcting IS actually done in number 4, and number 5 is hollow. So a cat back system would replace all, piping after number 5 right?

[nrcooled]

Just to throw this out there I noticed a pretty good differece when I bypassed my cat. &nbsp;the car breathes much easier and got a nice throaty tone. &nbsp;She felt like she had more in the top end

[rampid360]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Grant @ July 02 2002,01:36)</td></tr><tr><td id="QUOTE">the one under the car is the fake cat.

gains are marginal, usually not worth money spent.</td></tr></table><span id='postcolor'>
Sorry, i just gotta be a smartass here. &nbsp;They both seem to be under the car &nbsp; <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=''>

Anyway, i agree and would have to say if you MUST fiddle around with this area, get a high flow cat. &nbsp;Cars are designed to meet tree-hugger standards, and thus are built with backpressure from the cat in mind. &nbsp;Removing too much backpressure is horrible for your valves and will, sooner then you think, do MUCH more harm then good. &nbsp;Not worth the money, time and effort if you ask me.