Does my 240 have two mufflers!?!?

[AlligatorBling]

I have a 93 240 SE fastback, im thinking about putting a performance exhaust system on it. Today I looked up under the car to check out the stock exhaust and noticed something very strange, I saw what appeared to be two mufflers under the car... One a ways after the cat converter, and one at the rear of the car... What exactly is that other thing I saw before the most rear muffler? For my performance set up, I'm more than likely going to go with 2 1/2 pipe from the cat and a flowmaster 60 muffler. What I need to know is will it hurt anything if I take the other muffler off, or whatever it is off, and run just the pipe from the cat to performance muffler? Any help would be greatly appreciated... Thanks.

-Ryan
93 SE fastback

[Kreator]

called a resonator. Very useful in reducing noise. Removing it won't hurt anything (may even increase performance) but you'll be loud... unless ofcourse that's what you want...

[AlligatorBling]

Thanks man <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/biggrin.gif" border="0" valign="absmiddle" alt=''> I sure do appreciate it! As for the loudness, I can deal with it if I get alittle more perfomance out of it, performance is what its all about! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'>


-Ryan
93 SE Fastback

[240sx2Nur]

Yeah, I have 2.5 piping to an Apex_i N1 muffler, with no resonators. Its very loud, but I never found it annoying, especially when you get to see the look on peoples faces when you give it full throttle &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/hehe.gif" border="0" valign="absmiddle" alt=':hehe:'>

[SilviaDriver]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (240sx2Nur @ Dec. 06 2002,5:44)</td></tr><tr><td id="QUOTE">especially when you get to see the look on peoples faces when you give it full throttle <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/hehe.gif" border="0" valign="absmiddle" alt=':hehe:'></td></tr></table><span id='postcolor'>
yea, they will be WTF!? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/crazy.gif" border="0" valign="absmiddle" alt=':crazy:'> damn its slow! HAHHAHA <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/laugh.gif" border="0" valign="absmiddle" alt=':laugh:'>

[Silviaholic]

Question! Will a resonator create enough back pressure to deem a 3" piping system useful. My question is simple.

======[__]====[_]<
RES MUFF
Being that a N/A 4cly would perform like shit with 3" piping due to lack of pressure, will adding a resonator cause enough resistance to make the 3" system efficient? Being that I would like to have the exhuast done soon; I could just create a section of straight pipe and replace the res with the straight when I go turbo...


good vs. bad idea?

edit:

exhuast macro fauked up

[Kreator]

It's the flow you have to worry about, not the backpressure. With 3" exhaust you'll be flowing through the area approximately 1.44 times larger than if it was 2.5". Our cars just don't produce enough exhaust. Backpressure comes into play when you are flowing more than the area. So technically speaking the resonator will have no effect on reducing the low end loss. It will trap the air that goes to it and it will some of the energy hitting the walls and go on its way. The flow will still be about the same though.

The resonator will give you like maybe .5hp. It's basicly the same effect as removing the muffler, except the muffler is more restricting than the resonator.

[AlligatorBling]

Do you guys thing I should stick with the stock exhaust pipe size, and just cut the resonator out and put a straight peace there to replace it, and replace the stock muffler with the performance muffler, rather than having larger diameter pipe put in from the cat back to the performance muffler? Which is would be the best idea, I plan on installing a performance intake as well so im hoping that will help it out too...I dont want to loose to much back pressure that it robs me of power ya know? Any suggestions would be greatly appreciated, thanks.

-Ryan
93 SE Fastback

[Silviaholic]

I wouldnt go above 2.25 if you wanted to do your system. My thought is as follow: Unless you are doing the COMLETE flow system from intake filter to tip, dont do it. Its a waste of time in my opinion. The system shoudl perform ALOT better when it is completely done all at once.

edit:

Kreator: &nbsp;What do you think I should do in my situation. &nbsp;Like I had said, I would like to have the complete flow system created while I am N/A and not have to have a new system recreated when I go KA-T

[AlligatorBling]

So you think I should run larger than 2.25 pipe all the way back from the manifold...? Or just back from the cat? im a bit confused now <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/confused.gif" border="0" valign="absmiddle" alt='???'> I plan on installing a ram air intake after xmas, then later upgrading it with a cold air extension... How much power do you think I will feel after installing just the performance muffler with 2 1/2 pipe from the cat ... and installing a injen ram air intake system? Because thats more than likely what i'll end up doing. Thanks for any help &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=''>

-Ryan
93 SE Fastback

[Kreator]

Silviaholic - it would depend on what psi u are running. I'm going to run 4psi (or 7 if i get enough money with the tax return to get the ecu) and i'm doing 2.5" mandrel bent with high flow cat and resonator.

It will also depend on what you want from the car. If you want straight out performance later on, then get 3" system right now, live with it for 2-3months. although it's annoying as hell. i took a ride in a friends 240 with the 3" dragger and my head was hurting like 2 mins later. He says he's fine though. On the other hand i didn't feel any reasonable low end loss. Might be for the reason that he has i/h/e and his car just revs alot quicker. In my opinion it's more about whether u wonna be hella loud and if u can stand the friggin sound it makes. But if it's just a performance daily driver not runnin more than 10psi, then just get 2.5" mandrel bent and forget the problem.

Oh, and custom performance shops don't do 3" mandrel bent. So be ready to spend some $$$. If u decide to do 3" crushed, 2.5" mandrel is better. And definately get yerself a high flow cat.


AlligatorBling:
Injen short ram - 2-3rwhp
Injen short ram + CAI - 5-6rwhp (together)
we already have a 2.25 crush bent. So get mandrel bent 2.5" and you'll be fine for na. If you are going to be doing headers, then get a high flow cat. If just the exhaust and intake, don't bother and run a catback.

[AlligatorBling]

Do muffler shops have machines that can do mandrel bends or do you have to order a catback kit from a performance company to get a pipe with those bends? My whole reason for going with the idea of buying just the muffler then having the pipe installed is to save money...

[Kreator]

Some shops do up to 2.5" mandrel bent piping. Depends on whether you luck out or not. I have one around my place that does 2.5" mandrel bent piping for $220 if u provide the muffler. So it's way cheaper than a catback but expect the quolity to be worse. The only reason i'm doing custom piping is that i think all the mufflers on the current catbacks for our car suck.

[91CRXsiR]

i got my mandrel piping 2.25' done for about 120.00 USD, in west covina. i love it..

except the REALLY loud noise and some bastards stole my silencers [ what kind of a world do we live in? ]

hrm.. resonators huh?... how much more restrictive is it? do you need one to be smog legal.. wouldnt a silencer work kinda like a resonator?

[Kreator]

Umm honestly, i think silencers are the gayest thing ever invented. You have 2.25 catback running and then u plug up your muffler hole with a silencer that only 1.5" in diameter.... am i seeing something wrong here? But yeah... it does whatever silencers do.

Silencers are way less restrictive than the mufflers themselves, so i'd say you won't feel any diference if u had one in place.

As for being smog legal, i have no clue, but i don't see how it would have any effect.

[Silviaholic]

Kreator- &nbsp;Your plan seems finhe, but I hate beingl ound like those can draggin assfaces, so i will probably get the 3' with and res and a muff.... damn talkin all this muff and not one smart remark...my how the board has matured...

but anywho, &nbsp;will a res and muff quite a 3" system down to the bearable level? &nbsp;Just until the KA-T comes into play...