The inserts cannot be flowed as a normal muffler since they actually draw air through when in operation. This is why they must be close to the engine and have hot air flow. The unit flows more air in use than on a flow bench. The assembly actually draws air through the exhaust. The function is unique and that is why it was granted a patent. It is not just a perforated tube and baffle assembly.

Each application will be different. Typically the 2 disk insert will reduce sound 3-5 decibels. The 3 disk insert will reduce sound 5-7 decibels. *See application chart for the most efficient insert size. An over sized exhaust system, even with the insert installed, may be louder than desired, because the inserts flow so well.

IMPORTANT NOTE: A rich fuel mix will create a much louder exhaust note than a properly tuned system. If there is a lot of black soot or carbon deposit on the exhaust or insert, this is an indication that the fuel mix is rich and should be properly adjusted for best performance.

In race applications if you meet the sound requirement without an insert, this is an indication that your collector size is marginally small, running an insert may cause restriction or power loss.

In some race applications, one disk is sufficient to meet the decibel requirement. Simply cut one disk off of a two disk insert.

First, check your air/fuel mix. (see above)

Install the plugs and restrictors on the center tube. Start with the restrictor plug (the plug with the pre-drilled hole) on the inlet side of the insert. If more sound reduction is desired, install the solid plug on the exit or end of the insert.

You can also pack in between the disks with a Stainless Steel Wool. This is recommended for street applications only.

Crank case vent tubes should be placed in the collector AFTER the insert. Installation in front of the insert may create oil blow by. It is also good to use a check valve in the vent tube.

The inserts work off of the strength of the exhaust pulse as well as the heat of the exhaust. In race applications the Inserts are best installed in the collector or in the extension pipe after the collector.

In street applications the inserts should be installed in the system after the catalytic converter and before the rear axle.

The further back the inert is installed, the less effective they are at reducing sound.

Yes. CC Inserts work well at reducing resonance and additionally reducing sound of an existing muffler system. In this case the inserts can be installed before or AFTER the muffler, even in the tail pipe.