Question of the day. In michigan Silver Lake Sand Dunes we have a 96 dec. sound limit. They test us at 2500 rpm 20" from the exhaust outlet. What muffler is going to keep a LS2 w/o turbo's at or below that level. Also they can't be a straight thru design. Turbos will generaly pass.

The quietest setup I've ever seen was on HV's rail, and and they were actually a straight thru design.


It was a single muffler, one exhaust tube entered on the top and exited the top, directly across. The other tube came in at the opposite side bottom, and exited straight out the other side bottom.

I'll see if I can find a previous post on it. Super smooth and very low tone to it. The trick is to cancel the exhaust pulses with other pulses 180* out of phase without introducing excessive backpressure.


Here's a pic of one like it from Summit:

does that muffler have separate chambers for each direction?

I'm not sure about the separate chambers, and the one in the pic is just similar looking, I don't even know if it is the same brand.

I just recall that it looked similar, had a very smooth, quiet tone at idle and seemed to have very little backpressure while being very quiet.

Here you go, here's an actual pic of the muffler in his rail.




Here's the thread talking about it.


mufflers

[attachmentid=94908]Heres ours, can't comment on the DB's though.

thats a realy trick setup (for the limited room in a taildragger )

i realy like them Magnaflows; legal, stainless, fairly quiet and a downright sexy sound


here is how they look in our cars;

Thanks for the props guys.... I like it. As fara s chambers, they aren't chambered. It's a straight thru design. Has a nice smooth tone, and still not loud. We can carry on a conversation while driving.

^^ i love a resonably loud V8, but HVs car is quiet and sounds effin awesome! still has that attitude it should have but not at all intrusive

We are trying to build intrest in a slip on type muffler similar to what is on headers. What would everyone think about a muffler that you could slip on to your original header and bring sound down to a legal limit. In fact how about and 500Hp LS2 that idles at 80 dbs and is only a 100 at 3,000 rpm. This 22" at a 45 degree angle from the ehxuast? You would need to remove your current silencer to add this one. Oh and the most important part is No power loss with actuall gains.

[attachmentid=95012]



Here is Mine ..........Super quiet

I'd buy it

We are getting ready to offer a kit for so this ca n be done with little mods on almost all cars.

FYI. Be carefull with these types of mufflers. Make sure it is designed to have a inlet and outlet on each side of the muffler. Alot of the mufflers on the market like these are dual in dual out and while it may be quiet they tend to fail pre maturaly and can cause some major restriction becuase the exhaust is actually being forced back into the other side.

ADDICTED

Here is a similar setup that Tripod did:


And another on a mid-engine:


I will be having Tom build some type of two into one on my new DanZio 600HP mid-engine. Looking to make it as quiet as possible without loosing too many ponies.

ADDICTED are you from Gibson Exhaust? I talked to them a couple of weeks ago about the michigan noise restrictions. I would like to see the mufflers your talking about.

These are going on my buddies new car, the shorty's.

I would be for them. The slip on Camco's I have now are a bit much.

Everything I have seen has been for V8's, anybody got one for a subie?

I am using the Magnaflow, but the 9" shorties wont meet the db sound you need, these are on the loud side, but they sound good.

that muffler has a nice color looks like it got realy hot

Exactly how do welded in baffles fail prematurely.

anyone ever heard of spintech???
i kno its got a cat, but my suburban sounds good, cousin has them on an SS silverado, supercharged with headers, no cats dumps out in front of the rear end...it has resonance, cuz the cab, but outside it has a nice muscle car sound, and a boat sound goin down the road especially with the supercharger whistle, im thinking of getting them put on my el camino they also have a muffler that goes in and out on the same side, like has a spliter wall down the middle, legnthwise, of the inside of the case, then flows out and around to the other side, if thats something your interested in i like mine...good sound, beats any flowmaster (too common) or magnaflow (fiberglass burns out...loses tune)...but hey maybe im bein dumb

Its not stainless, its the cheap one

My post wasn't directed towards the muffler pictured as I do not know exactly how the internals are, but imagine the right side being a dual inlet and the left side being a dual outlet. The right inlets would have both pipes protruding into the case about 6". At the 6" there will most likely be a chamber wall. Moving left there would be an open chamber and then left side would mirror the right side. Where the problem would accrue is when the two top pipes are used as inlets the exhaust will meet in the center and create a hot spot because the exhaust is not being directed to the lower exits, but being forced. Because of the excessive heat over time sooner than normal the material will crystallize and become brittle. Much like headers on motor home over time. They tend to look like the material is actually melting or bubbling. Because of extensive heat over long periods of time.


I would aslo steer clear of a non fully welded case mostly seen in packed mufflers. When you take a muffler case or chamber wall and press then into the case it will at first seem like a tight fitting connection. As soon as the muffler builds heat the metals will expand. When the metals expand, because of different thickness and shapes the outside case will expand more than the inside chamber wall creating leaks and worse of all rattles. This is why you need a fully welded case.

The slip on mufflers will look very similar to the ones in my sig.

Thanks for the clairifacation .
I can see where the inlets could cause a hot spot and fail.

While this is a good muffler in the right application, it is not a good choice for the application at discussion here. First of all, it is not a good looking unit, and we all know that we can't have that! Second, it will fall apart pretty quick, due to the method of construction and material thickness.

In case you are wondering, the right application, in my opinion, is a high HP drag race car that needs to be below 95db. And, it is under the car where it can't be seen.

Here are a couple pictures of the headers with a single muffler. This will be offered as a kit.

I'm running the Borla shorty's. It's a great collector, sound, performance, and construction. But, I don't think your gonna see the Db. number's any enforcing agency is asking for.

The SpinTech mufflers are also good for Sprintcar applications. On some engines, they make more power than the FlowMasters.

I've never been a fan of the Flowmaster mufflers, something tells me that having the baffles shaped like that is unnecessarily restrictive. I saw a cutaway of another muffler with spiral shaped baffles, same deal, looked pretty restrictive to me.

Sound waves get cancelled out when an equal intensity pulse 180* out of phase hits it. There was a company that was working on using a mike and a transducer to create a noise cancelling exhaust pipe, exactly like the noise cancelling headsets. The video I saw showed a car with knobs on the dash which allowed you to vary the volume and tone of the exhaust note by varying the intensity and phase of the transducer output.

Straight pipe with no baffles = no extra restiction, no glass acking to blow out. Although some backpressure is a good thing for driveability.

That was a while back, don't know what happened to it.

Thats sounds very intresting and makes complete sense.

As far as I know, there was a problem with the lifespan of the electronics in the muffler. The corrosion and acids produced by the exhaust would ruin the electronics over a relatively short period. I feel that someday it will make its way into production.

I don't think he cares.
He won't have any friends in camp though.......

[size=7] THIS FAMILY BELEIVES IN WHAT THEY DO!!!!!

GO GIBSON OR GO HOME!!!!!!!!!!!!!