Anyone have a pic of a gutted oem or non-oem muffler? Is my ebay one restrictive?
I have a 3" nismo replica ebay exhaust on my car and I found this picture of my ebay muffler opened up:

Does this look like a very restrictive muffler for a Vortech setup aiming for 400whp?
Does anyone have a pic of the internals on an oem muffler? I have an oem muffler at home but I don't want to open it up if I don't have to.

Does this look like a very restrictive muffler for a Vortech setup aiming for 400whp?
Does anyone have a pic of the internals on an oem muffler? I have an oem muffler at home but I don't want to open it up if I don't have to.
i dont see why you cant achieve 400whp with a vortech with that exhaust. Leave it alone, if you dont have one already get test pipes and an aftermarket ypipe (they sell one from ebay that mates to that one you have).
I have the same exhaust SRS with the ypipe and i love the sound. And i plan on getting a Vortech sometime this year.
I have the same exhaust SRS with the ypipe and i love the sound. And i plan on getting a Vortech sometime this year.
I already have megan racing long tube headers and Y pipe.
Looking at the pic of the ebay muffler, it seems that only the perforated tube in the center chamber will get the exhaust gases out...the rest is just for sound.
I dunno, I'm no muffler expert.
Looking at the pic of the ebay muffler, it seems that only the perforated tube in the center chamber will get the exhaust gases out...the rest is just for sound.
I dunno, I'm no muffler expert.
Trending Topics
The picture in your original post is my work.
That muffler cut open (in the first post) is an ebay knock off Megan racing exhaust. The tubing is 3" diametre from the Y-pipe going in to the muffler.
My issue with it was boost not holding on spring pressure all the way to red line. The boost would drop off at 5000+rpm. I had removed the muffler and put a 2' piece of straight turbing in, and my boost stayed even all the way to red line. So the muffler did not flow well enough for that.
I put the muffler back on, got a BC and dialed it in until I had 8 psi to red line. The result was 402whp, with a quieter than stock exhaust.
That muffler cut open (in the first post) is an ebay knock off Megan racing exhaust. The tubing is 3" diametre from the Y-pipe going in to the muffler.
My issue with it was boost not holding on spring pressure all the way to red line. The boost would drop off at 5000+rpm. I had removed the muffler and put a 2' piece of straight turbing in, and my boost stayed even all the way to red line. So the muffler did not flow well enough for that.
I put the muffler back on, got a BC and dialed it in until I had 8 psi to red line. The result was 402whp, with a quieter than stock exhaust.
The picture in your original post is my work.
That muffler cut open (in the first post) is an ebay knock off Megan racing exhaust. The tubing is 3" diametre from the Y-pipe going in to the muffler.
My issue with it was boost not holding on spring pressure all the way to red line. The boost would drop off at 5000+rpm. I had removed the muffler and put a 2' piece of straight turbing in, and my boost stayed even all the way to red line. So the muffler did not flow well enough for that.
I put the muffler back on, got a BC and dialed it in until I had 8 psi to red line. The result was 402whp, with a quieter than stock exhaust.
That muffler cut open (in the first post) is an ebay knock off Megan racing exhaust. The tubing is 3" diametre from the Y-pipe going in to the muffler.
My issue with it was boost not holding on spring pressure all the way to red line. The boost would drop off at 5000+rpm. I had removed the muffler and put a 2' piece of straight turbing in, and my boost stayed even all the way to red line. So the muffler did not flow well enough for that.
I put the muffler back on, got a BC and dialed it in until I had 8 psi to red line. The result was 402whp, with a quieter than stock exhaust.
Are ALL 1in/2out mufflers this way inside?
Bigger IS always better. Iv got a 3" in/out Dynomax Superturbo, which is supposed to flow pretty good, when i take out the muffler I gain about 2-3psi. Im willing to be with a 4" muffler I wont have that issue.
The problem is that I don't want TOO much flow because S/C's need some backpressure ( and yes, I said backpressure...not velocity ) and I'm afraid an exhaust like the X02 will simply flow TOO much.
As a matter of fact, I saw someone on this very forum who added a cat converter and he GAINED 30whp or something like that...can't rememeber who though.
It has to do with the overlap on the N/A cams that allows for unused fresh air to simply bypass the combustion chamber and go straight through the exhaust. Something that doesn't normally happen on N/A nor turbo cars.
That was me...
https://my350z.com/forum/8386089-post1.html
I believe this only applies to Vortech and maybe other supercharger kits; there is a threshold where you start losing instead of gaining hp as you free up the exhaust, and where that point is I am unsure of (my setup uses ART Pipes with the single motordyne XYZ cat; its possible that I may lose hp if I went more restrictive with a standard dual cat setup...but I am definitely getting more power than with the straight pipe on the XYZ) ...
This definitely dosen't apply to N/A, according to Tony at Motordyne, as for turbos, I don't know but I would put my money on the less restictive the better on that setup as well...
Vortechs are just weird...
https://my350z.com/forum/8386089-post1.html
I believe this only applies to Vortech and maybe other supercharger kits; there is a threshold where you start losing instead of gaining hp as you free up the exhaust, and where that point is I am unsure of (my setup uses ART Pipes with the single motordyne XYZ cat; its possible that I may lose hp if I went more restrictive with a standard dual cat setup...but I am definitely getting more power than with the straight pipe on the XYZ) ...
This definitely dosen't apply to N/A, according to Tony at Motordyne, as for turbos, I don't know but I would put my money on the less restictive the better on that setup as well...
Vortechs are just weird...

Last edited by 350z006; May 28, 2010 at 08:08 AM.
The picture in your original post is my work.
That muffler cut open (in the first post) is an ebay knock off Megan racing exhaust. The tubing is 3" diametre from the Y-pipe going in to the muffler.
My issue with it was boost not holding on spring pressure all the way to red line. The boost would drop off at 5000+rpm. I had removed the muffler and put a 2' piece of straight turbing in, and my boost stayed even all the way to red line. So the muffler did not flow well enough for that.
I put the muffler back on, got a BC and dialed it in until I had 8 psi to red line. The result was 402whp, with a quieter than stock exhaust.
That muffler cut open (in the first post) is an ebay knock off Megan racing exhaust. The tubing is 3" diametre from the Y-pipe going in to the muffler.
My issue with it was boost not holding on spring pressure all the way to red line. The boost would drop off at 5000+rpm. I had removed the muffler and put a 2' piece of straight turbing in, and my boost stayed even all the way to red line. So the muffler did not flow well enough for that.
I put the muffler back on, got a BC and dialed it in until I had 8 psi to red line. The result was 402whp, with a quieter than stock exhaust.
From what I've seen, my $300 exhaust is identical to Nismo's $1000+ exhaust....so how exactly does buying a "real" exhaust make sense? I could even change out the muffler to a high flow one and I'd still save a HUGE amount of money. Just because I have a vortech doesn't mean I like to throw away money.
Thread
Thread Starter
Forum
Replies
Last Post





