[Tom Hand]

I found my Hooker AeroChamber cutaway and thought I'd share some images that show why these things flow as much air as they do.

1. This one is looking into the inlet. Instead of the flat plate you see in offset chambered mufflers, you can see the nice curved cup Hooker's engineers devised.

2. This shows the top view of the inlet cup/flow director which clearly shows why it gets the exhaust smoothly into the interior.

3. This is the Helmholtz tuning chamber which they carefully sized to try to eliminate certain frequencies. I have not calculated what it is so can't tell you this.

4. This shows the expansion chamber with perforated walls to allow the sound to be absorbed into the glass fibrous material. Had the fiber mat been maybe 0.5" to 1.0" it would have toned the sound level down some more but they are room limited so they used ab0ut 0.25" to 0.375" thick matting.

5. The last one shows a side view looking over the top of path out of the muffler and you can see that once again, instead of using a flat wall, the designer used the same cup-like chamber to gradually and smoothly direct the gases out of the muffler.

How well does this work? Here are some comparison numbers.

Hooker “AeroChamber”, airflow as compared to open pipe: 73%
Flowmaster 50 Series “Delta Flow”, airflow as compared to an open pipe: 53%

The sound level on the Aerochamber was only 2 dBA quieter at low speeds. This is due to the small chamber with thin mat to absorb the sound; this muffler is not dependent upon interference to cancel the sound.

Hope you enjoy these!

[Tom Hand]

And here it is all together so you can see the entire package.

[David Holmberg]

I had an Aerochamber system on my 99 SS Convertible, it sounded very good. Unlike the crappy sounding Flowmaster system that came on my 98 SS.

[Tom Hand]

Dave, I think they sound good, just a bit loud w/o cat. converters but they do work very well don't they?
Tom

[PLAY400]

I have them on my 462 55. Louder than my dynamax but they haven't split on the factory bends and are alot older. Still have to drop the center section to see how bad the problem is but 1 is split almost the whole length. Then I'll be on the phone to Walker for a refund as I heard this is a design problem.

[Tom Hand]

These Aerochambers are tough and made of thick metal for sure.

The long body Welded Ultraflo has a flaw and some had stress cracks in the stamped ID names. Walker is honoring their warranty so for sure, get back with the Dynomax people.

I am going to shoot more close-up images of my other cutaways so stand by.

[David Holmberg]

Originally Posted by Tom Hand

Dave, I think they sound good, just a bit loud w/o cat. converters but they do work very well don't they?
Tom

Mine had cats, but the sound was just right with the top down, and very quiet with it up. Plus having the muffler at the rear of the car probably helped too.

[Laguna454s3]

Thanks Tom

I would suppose that these flow exceptionally well with a center inlet/outlet, thus avoiding turbulence in the inlet flow direction area.

I like the sound of these in your testing as to me they resemble the Old 1991 AP Xlerators that both you and I have. They have a deep burbling tone.

John

[Tom Hand]

Hi John,
Yes, I too think they would let the exhaust rip right through with center in center out BUT I think the sound level would also reflect the lack of any impedance and restriction. They would still be quieter than no muffler that is for sure.

You know, my old XLERATORs have a higher pitched tone, with no resonation whatsoever. They reminded me of stock HEMI mufflers tuned to not rumble but instead crackle. I'll find photos shortly and post them for others.

Tom

[Z Code 400]

Tom,

The Helmholtz tuning chamber (HTC) creates an effect, similar to blowing across the neck of a soda bottle. The frequency of the engine's explosions causes resonance in the exhaust pipe and the HTC is designed to absorb resonance and noise volume in such a way that these sounds are cancelled and become inaudible.

[theYman]

I did have a set of flowmaster 40's but was tired of the resonance at low speed cruise.I now have these aero chamber mufflers on my car. I really like the sound and they really flow; car even seems faster. My car also has a set of electric cutouts. I put them right behind the mufflers as the pipe turns up. I love the sound now...everyone asks what mufflers are those... SOMEDAY,Ill take a video and post it.
TRENT

[b-man]

Closed per the thread starter's request.