This kit offers higher levels of rotor sound (whine) within the cabin due to the direct path from the inlet through the firewall and the larger ID.
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This Kit requires that the firewall is drilled. Contents:
1 3/4” hole saw
1 3/8′′ step drill
1′′ straight hose barb
1 x diaphragm cap
1 x Blade
Sound Tube
2 x rubber Grommets 1 Large 1 Med
1 x Zip tie
Cut a round hole appox 2.5-3” in the marked location with supplied razor to prepare for drilling.
Cut carpet should be in the red circle outlined for best fitment.Use a center punch to mark the drilling point for the 1 3/4” hole. Drill in the middle of the marked location that carpet was removed. After using the center punch to mark the drill entry point, drill using the supplied hole saw at low speed and using a light oil for lubrication to avoid (overheating) and damage to the drill bit.
Make sure the drill and hole saw is flush with the Firewall sheet metal as not to catch and edge and damage drill bit. It’s recommended to stop twice to re-oil the hole saw teeth.
Note for best fitment hole should be drilled in the red circle locationWith provided step drill bit, drill out the inlet pipe to 32mm or 1 ¼” at the red mark location in the picture below except on the bottom, 180 degrees from the red reference mark. This is the second to the last step on the drill bit. Cleanup the inside of the drilled hole so it’s uniform and smooth and install the small rubber grommet.
Use light grease and install the 90 degree 1” hose barb fitting (this is a tight fit). Attach the sound tube to the hose barb end of the 90-degree fitting in inlet pipe. The other end of the sound tube (marked firewall end) is inserted into the firewall grommet.
Install the supplied large rubber grommet working into the 1 3/4” hole which was cut in the firewall. Use some grease on the bare metal edges for protection. Add some grease to the grooves of the grommet to prevent corrosion.
Install the sound tube through the firewall hole with grommet first, it should be possible to fit your entire arm into the space and your hand all the way to the firewall. A little grease or WD40 inside the grommet and on the tube end will aid in pushing the sound tube hose end through the grommet in the firewall.
TIP: Electrical tape can be wrapped around the end of the sound tube hose to reduce the tube diameter and aid insertion into the grommet
It may be necessary to go inside (the foot well area) to pull the hose end through to a depth of about 1 ½ “.
Image:
Electrical tape used to narrow the end of the tube to add in install through grommet.
Sound tube installed in 90 hose barbThe rubber diaphragm must be used to seal off the sound tube from the inlet path. This ensures the MAF and calibration is not changed. Use a little WD40 on the hose end and push the cap into the end of the sound tube.
Warning: failure to install the diaphragm cap properly could result in unmetered air and poor running condition.
We appreciate your business and hope you enjoy the increased rotor whine!
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