NZ Hot Rod – August 2019

40 > NZ HOT ROD AUGUST 2019

strategically located in order to cancel
noise by separating, then recombining
pulses. Finally, a low-pressure balance
chamber is usually incorporated at the
rear of the muffler. This chamber is
designed to block atmospheric pressure
from moving back into the system.
Hooker Headers’ high tech take on
this is their Aero Chamber muffler.
Here, as exhaust enters the muffler,
it encounters an aerodynamic lens
which directs sound pressure waves
into what is called an “acceleration
chamber”. The stepped acceleration
chamber then increases the velocity of
the exhaust, promoting maximum flow.

An internal resonance chamber coupled

with a tuning tube cancels unwanted

frequencies and amplitudes. In place

of louvers, these mufflers use a large

stainless chamber perforated with small

holes. This is the sound absorption

chamber which quells high frequency

sound waves. Since there are no louver

edges dropping into the exhaust flow

path, there is no restriction in the flow

of exhaust gas. But at the same time, the

perforations still allow the sound to be

absorbed. At the tail end of the muffler,

another aerodynamic lens direct sound

pressure waves out of the muffler.

The result of the Aero Chamber

arrangement is maximum scavenging

and added torque in many applications.

In terms of construction, the internal

chambers are built from stainless steel

while the case is constructed from

16-gauge alumini sed steel. As far as

sound is concerned, this muffler will

not drone at cruising speeds and the

internal sound absorption chamber

eliminates high frequency sound

waves which tend to make that tin can

sound we’re all familiar with. What

you’ll end up with is a deep throaty

exhaust note. Typically, the Aero

Chamber also an extremely high flowing

design – second only to the Maximum

Flow design mentioned above.

Footnote: Check with your certifier as to the

suitability of these products for your vehicle

in reference to NZ sound regulations.

SOURCE:

Hooker Headers

Holley Performance Products

1801 Russellville Road P.O. Box 10360

Bowling Green, KY 42101-7360

Website: http://www.holley.com

PH# 270-782-2900

Maximum flow mufflers are not “directional”. That means you can install them in any direction you

choose (there is no dedicated “IN” or “OUT”).

Aero Chamber mufflers are directional (obviously). They can only be installed in one direction.

On the outside, the Aero Chamber and
Maximum Flow make use of the same
heavy-duty 16-gauge aluminised steel
case. Both measure 14.375-inches long by
10.625-inches wide by 5.00-inches tall.