Anyone with Stainless Works exhaust system with the turbo chambered mufflers?

[XfireZ51]

Like many on this forum, I did my bit when it comes to experimenting w various exhaust systems. Over time, I've "evolved". The exhaust system changed as the power levels changed (increased). So here's a summary of how things were modified.

1. stock motor, stock exhaust
2. Stock motor, B+B 3rd Gen cat back. ~ 340rwhp.
3. Stock motor, Watson 1 7/8"headers, B+B 3G. Drone
4. Ported Top End, headers, B+B 3G. Drone 387rwhp.
5. Ported Top End, headers, MagnaFlow cat back. Sweet exhaust note, ~400rwhp.
6. Ported heads, Intake cams, headers, Xpipe, MF muffs. Drone. ~420rwhp
7. Ported heads, I/E cams, headers, Xpipe, MF muffs. Drone ~440rwhp
8. Ported heads, I/E cams, headers, Xpipe, DynoMax, NPP tips. ~454rwhp.

HP numbers are all SAE corrected.

With tuning and using the NPP on/off, drone is pretty much eliminated. In fact, cruise is nice even w both tips open. With two tips open, the exhaust takes on a basso profondo note. The difference between open/closed tips is very noticeable at idle from inside the cabin.
I would also recommend installing fiberglass insulation or some type of sound deadner in the spare tire carrier.
THAT has really made the exhaust note very tolerable by dampening any vibration coming from the floor of the hatch area.
If you have a stock motor, I like the MF cat back. Did not find that resonator restriction really made a difference. It appeared fine supporting up to 400rwhp.
My one complaint is the hanger setup for these mufflers. Plainly, they suck and need to be modified. But the 3" SS pipe that came w the cat back is still part of my exhaust.
As before, I will emphasize the importance of tuning, and I mean part throttle/cruise, in taming the drone. Drone happens when opening the throttle where vacuum drops (ie higher MAP) and exhaust gets blubbery. So getting the AE ( pump shot) right and leaning out the mixture in that part of the fuel table goes a long way to reducing/eliminating the drone.

[HAWAIIZR-1]

Originally Posted by Gunny

I've also been interested in this mod to the LT4 system (or late LT5 system for that matter) ... I believe the X-Pipe "might" be an improvement. Talked with Tony D. at BG and he's experimenting with an H pipe and that sounds promising also. I would really like to hear/ride in a Z with the same setup I have except with the X-Pipe or H-Pipe replacing the resonator.

I think the next thing I want to try is cut-outs and perhaps that will be the last step. Each time I change something I swear it will be the last change but then the "bug" bites and I can't wait to try something else. One concern (fear?) is that I will arrive at an acceptable system (sound, performance, etc.) then take it one step too far. I've already done that a couple of times and it's frustrating ... but I suppose the "experimentation" journey can be fun at times ...

Thanks for your thoughts George. I was trying to do some research on the LT4 resonator and an X pipe that would work to replace the LT5 resonator. My fear is that here comes the drone and not sure what exactly makes or breaks my level of tolerance. On one hand thinking to just leave it alone or just go with Corsa and deal with raspy. The other is to just put cut outs, but not sure what that sounds like and still have the choke point of resonator.

I received this back from SW rep about their system with the chambered mufflers:

XXXXXXXXXXXXXXXXXXXXXXXXXX


From: Joe Nagle [mailto:joe@stainlessworks.net]
Sent: Monday, June 15, 2015 5:13 AM
To: Craig
Subject: Re: ZR1 Exhaust

Hey Craig,

The design of the mufflers is one single 3" ID inlet with multiple perforated tubes that lead to the dual 2.5" outlets. Surrounding those tubes is 304 stainless steel wool packing that will never break down and blow out. This is our quieter setup for an exhaust. Drone is such a subjective term but I think you should be alright with this setup. Let me know if you have any further questions.

Joe

XXXXXXXXXXXXXXXXXXXXXXXX

Worst case scenario is try it and if I can't take it in regards to drone/resonance do the NPP Z06 valves to their mufflers. I really was trying to stay away from custom work as I don't have time to deal with that for another year.

Take care,
Craig

[HAWAIIZR-1]

Originally Posted by XfireZ51

Like many on this forum, I did my bit when it comes to experimenting w various exhaust systems. Over time, I've "evolved". The exhaust system changed as the power levels changed (increased). So here's a summary of how things were modified.

1. stock motor, stock exhaust
2. Stock motor, B+B 3rd Gen cat back. ~ 340rwhp.
3. Stock motor, Watson 1 7/8"headers, B+B 3G. Drone
4. Ported Top End, headers, B+B 3G. Drone 387rwhp.
5. Ported Top End, headers, MagnaFlow cat back. Sweet exhaust note, ~400rwhp.
6. Ported heads, Intake cams, headers, Xpipe, MF muffs. Drone. ~420rwhp
7. Ported heads, I/E cams, headers, Xpipe, MF muffs. Drone ~440rwhp
8. Ported heads, I/E cams, headers, Xpipe, DynoMax, NPP tips. ~454rwhp.

HP numbers are all SAE corrected.

With tuning and using the NPP on/off, drone is pretty much eliminated. In fact, cruise is nice even w both tips open. With two tips open, the exhaust takes on a basso profondo note. The difference between open/closed tips is very noticeable at idle from inside the cabin.
I would also recommend installing fiberglass insulation or some type of sound deadner in the spare tire carrier.
THAT has really made the exhaust note very tolerable by dampening any vibration coming from the floor of the hatch area.
If you have a stock motor, I like the MF cat back. Did not find that resonator restriction really made a difference. It appeared fine supporting up to 400rwhp.
My one complaint is the hanger setup for these mufflers. Plainly, they suck and need to be modified. But the 3" SS pipe that came w the cat back is still part of my exhaust.
As before, I will emphasize the importance of tuning, and I mean part throttle/cruise, in taming the drone. Drone happens when opening the throttle where vacuum drops (ie higher MAP) and exhaust gets blubbery. So getting the AE ( pump shot) right and leaning out the mixture in that part of the fuel table goes a long way to reducing/eliminating the drone.

Hey Dom,

Thanks for the detailed rundown that will help all considering any mods in general as well as the effect on components. It almost seems like X pipe equals drone....ha, ha and no surprise. Maybe those guys from Corsa are pretty smart after all with their H pipe built in and using a pretty free flowing resonator to still get HP without drone. I suppose they put a lot of research into it. I still have to hear that in person to know if I like it or not. The other thing is not knowing the future of my build. I am thinking I won't be pulling heads or putting cams in this car after going through that on my 90 and living here in Cali. I really have to get into this "tuning" stuff one day and have half of the things needed. I have stay at Holiday Inn, but don't feel comfortable any time soon to get into tuning 101 and beyond just yet.

Thanks for all the tips about insulation and will try to do as you suggest when the time come never thinking about the spare tire carrier. I wonder how a product like dynamat or something would work under the carpet on the inside too in the hatch area? Gotta run to work, but appreciate the info and tips.

[HAWAIIZR-1]

Thanks for all the replies and greatly appreciated. I decided to give up on the SW chambered mufflers and not what I am looking for after all. I was hoping more than one person on here had experience with them. I'm going to look into unchartered territory with my quest for the perfect exhaust (for me and this car anyway). Marc Haibeck's study and information about exhaust system sure does explain a lot and made me rethink everything about what direction I want to head in. He is truly awesome for sharing his expertise with so much of what he knows so we don't reinvent the wheel.

[XfireZ51]

Craig,

It's not that Xpipe = Drone, it's that lack of resonator = drone. GM eliminated the resonator due to weight and restriction on the C6 Z06. Instead they used an Hpipe and the NPP valves to tame the drone.

[HAWAIIZR-1]

Originally Posted by XfireZ51

Craig,

It's not that Xpipe = Drone, it's that lack of resonator = drone. GM eliminated the resonator due to weight and restriction on the C6 Z06. Instead they used an Hpipe and the NPP valves to tame the drone.

Hey Dom,

Got that and understand how important those resonators are with preventing drone. Not that the one on my B&B helps much....my gen III system drones like hell too. I understand there is a lot of science behind all this frequency stuff and spent some countless hours trying to read about it, especially on C4s. So many dynamics change things in the exhaust system. Mike100 spent countless hours offline sharing what he learned over the years with trial and error as many others have done too. He also confirmed too the NPP is the way to go and I really see why GM went that route. I had high hopes for the SW chambered system since they listed in a few places that there was no drone, but it seems otherwise. I guess the only true off the shelf system without drone if you like the tone is the Corsas.

Craig

[XfireZ51]

Porsche and BMW both use NPP valves.

[HAWAIIZR-1]

Originally Posted by XfireZ51

Porsche and BMW both use NPP valves.

German Engineering at its best and glad to hear GM jumped on the band wagon.

[HAWAIIZR-1]

Originally Posted by XfireZ51

Like many on this forum, I did my bit when it comes to experimenting w various exhaust systems. Over time, I've "evolved". The exhaust system changed as the power levels changed (increased). So here's a summary of how things were modified.

1. stock motor, stock exhaust
2. Stock motor, B+B 3rd Gen cat back. ~ 340rwhp.
3. Stock motor, Watson 1 7/8"headers, B+B 3G. Drone
4. Ported Top End, headers, B+B 3G. Drone 387rwhp.
5. Ported Top End, headers, MagnaFlow cat back. Sweet exhaust note, ~400rwhp.
6. Ported heads, Intake cams, headers, Xpipe, MF muffs. Drone. ~420rwhp
7. Ported heads, I/E cams, headers, Xpipe, MF muffs. Drone ~440rwhp
8. Ported heads, I/E cams, headers, Xpipe, DynoMax, NPP tips. ~454rwhp.

HP numbers are all SAE corrected.

With tuning and using the NPP on/off, drone is pretty much eliminated. In fact, cruise is nice even w both tips open. With two tips open, the exhaust takes on a basso profondo note. The difference between open/closed tips is very noticeable at idle from inside the cabin.
I would also recommend installing fiberglass insulation or some type of sound deadner in the spare tire carrier.
THAT has really made the exhaust note very tolerable by dampening any vibration coming from the floor of the hatch area.
If you have a stock motor, I like the MF cat back. Did not find that resonator restriction really made a difference. It appeared fine supporting up to 400rwhp.
My one complaint is the hanger setup for these mufflers. Plainly, they suck and need to be modified. But the 3" SS pipe that came w the cat back is still part of my exhaust.
As before, I will emphasize the importance of tuning, and I mean part throttle/cruise, in taming the drone. Drone happens when opening the throttle where vacuum drops (ie higher MAP) and exhaust gets blubbery. So getting the AE ( pump shot) right and leaning out the mixture in that part of the fuel table goes a long way to reducing/eliminating the drone.

Dom,

I was thinking to myself and doing the math. You have more hours than I can imagine perfecting your car and tuning it over the years. I hope to get to the point in my life that I can spend more time to learn and understand these cars. I can't remember the TV program I saw many years ago, but this guy had a C4 (back then I was not into them) and guessing it was an LT1 car or maybe it was a ZR-1. He made some crazy horsepower doing just fine tuning to many different components of the car. I can imagine that only a small percentage of our cars are really tuned to squeeze the max out of the car. In the old school days even though there weren't computers, if you matched the right components together from the entire set up and tuned it right it was like the stars aligned and you would hit the G spot to make the car scream. Well, I'm way off topic now and I guess okay since I am the OP.

Anyway, I guess my small way to say thanks for your invaluable input and insight as always.

Craig