The Exhaust Debate

[xray]

Hey Paul,

Any audio of your exhaust? I've had about enough of the Dynomax that came with my exhaust system from MSA. Hoped it would mellow some, but it stayed pretty raspy.

[peterc]

Due to circumstances beyond my control (read...no money) I was forced to improvise when my muffler unexpectantly departed my '83 ZX at speed. In order to prevent exhaust fumes from entering the cabin until I get around to replacing the entire system, I ran a piece of straight pipe where the muffler used to sit. So from the CAT back is just exhaust pipe.

The sound is throaty, but not loud at idle and normal acceleration, and has a wonderful V8 growl when you mat it. What it most definitely does not have is that annoying resonnance at certain RPMs that I keep hearing about with some systems.

Anybody ever purposely gone that route for their exhaust system?

[Weasel73240Z]

Hey Paul,

Any audio of your exhaust? I've had about enough of the Dynomax that came with my exhaust system from MSA. Hoped it would mellow some, but it stayed pretty raspy.

I killed my last video cam, and the clips I took with my phone aren't very good. I'll try to get one posted. The sound is very good. Deep and throaty at the low end, and it sound real good right through the powerband. No resonance, no popping.

The only thing that had to be done was a slight modification on the outlet of the MagnaFlow. The outlet tip is 2 pipes, one about 3-1/2" that surrounds the inner 2-1/4" pipe. The 3-1/2" pipe had to be cut down with a die grinder to get it to fit through the opening in the rear valence. Pretty easy mod though, only took about a half hour.

[Poindexter]

Due to circumstances beyond my control (read...no money) I was forced to improvise when my muffler unexpectantly departed my '83 ZX at speed. In order to prevent exhaust fumes from entering the cabin until I get around to replacing the entire system, I ran a piece of straight pipe where the muffler used to sit. So from the CAT back is just exhaust pipe.

The sound is throaty, but not loud at idle and normal acceleration, and has a wonderful V8 growl when you mat it. What it most definitely does not have is that annoying resonnance at certain RPMs that I keep hearing about with some systems.

Anybody ever purposely gone that route for their exhaust system?

My PO removed the rear muffler, leaving only the middle resonator with plain pipe the rest of the way, and then welded the entire length of the exhaust for some unknown reason, and due to his misunderstanding of the raw gas smell (vent piping, reservoir issues) he turned the pipe out hard left to exit just behind the LR wheel. I guess he thought he was smelling CO from the exhaust.

At idle my Z is quiet, even during normal acceleration (like I've EVER done that!) it is un-noticeable, but as the revs approach 3k- if you have your foot in it- it starts to really rip, and with the pipe outlet being mere feet from my ears it makes the car sound heavenly, especially when driving alongside a concrete barricade/divider. It makes the roar bounce straight back into my ears. Not ricey, very much a growl at first then a howl. And totally controllable, if you don't want to wake the dead or inflame the local constabulary. And very addicting. I 'm afraid to touch it and sent the exhaust back to the rear for fear of losing my "signature sound".

When I drive away from the regular Cruise-Ins I attend, some of the people actually head over to the road to hear me rip through the gears as I pull away. Hot rod people, too. As there are no inspection requirements for my car in NJ, I can't imagine ever having a normal exhaust with a muffler, ever again. It's the best of both worlds.

[Arne]

There are many ways to get nice sound. The original owner of my 240Z replaced everything behind the Y of the stock downpipe. Way low-tech and simple. Consists of 1-7/8" crimp-bent pipe, and a 24" generic glass-pack muffler where the resonator used to live. That's it - small pipe size, no rear muffler, just the single glass-pack. The sound is actually quite nice, not overly loud, no resonance, a mellow note reminiscent of early Jags or a 95-99 M3. So nice sound isn't hard to get.

[borini63]

Here's my exhaust.

What kind of muffler?

[SeafireXV]

If performance is your main goal all you need is a good quality header, either stainless steel or coated to take care of rust. A single exhaust pipe no more that 2 1/2" diameter and a good quality free flowing muffler like Flow Master or Magnaflow with a single outlet tip. You don't need a resonator on an L28 as they are not as raspy as the L24. Just use common sense and keep it simple. Z's seem to respond well to simplicity. Dual pipes are not necessary and just complicate things, and period mufflers like the Monza dual tip setup are more for looks than performance. Anyway, that's what I've learned over the last 40 years.   

[caltanian]

I went through three different exhausts before I settled on one that I like the sound of, and gives a nice buttometter gain in power. 

The previous owner had just clapped a few pipes together, and some sort of super turbo. It worked, but I was not a huge fan of the sound. The headers were also pretty beat up. MSA 3-2-1 headers and the super turbo exhaust. Nice sound. Little more refined, but nasty rasp. Added a magnaflow 14" resonator inline, and loved what it did with the sound, but felt it could be a little better still.

Settled on the resonator and magnaflow with a slash cut chrome tip. Nice, deep idle, clean and good around town, and when I step on it, makes enough noise I never regret putting the stereo out. Part of me wants to see what would happen if I put a dump pipe behind the resonator. Kinda a two stage exhaust.. Maybe a project for another time.  

But as she sits, it does feel like there's a little more power. This is likely aided by having the SU's done by Ztherapy, and just a proper tune at the same time.