2020 & Up GT500 Stage 2 Whine Mod to OEM Sound Tube Installation Guide SKU 455,461,465,470,877,977,1125,1200

2020 & Up

Stage 2 GT500

Sound Tube Installation

SKU 502

This upper kit offers increased levels of rotor sound (whine) within the cabin but does not require drilling through the firewall.

Connects to the OE cut sound tube at the firewall.

Connects to the OE cut sound tube at the firewall.

  1. Whine mod sound tube
  2. Hole saw
  3. 3 nylon spacers
  4. Blade
  5. 6mm nut
  6. Small diaphragm cap
  7. Grommet
  8. Straight hose barb
  9. 2 zip tie

Cut the OE sound tube in the middle at the point of the yellow line (see image).

Install in the stock location using the supplied 6mm nut. Note this can also be cut in place with small saw or razor clippers.

The OEM sound tube will have either a white or black foam baffle that needs to be removed before diaphragm cap install.

Remove the 3, 10mm nuts from the accelerator pedal and remove the pedal.

Once pedal is removed cut around the opening of the sound tube entry hole (see diagram) using the supplied blade.

Check that the sound tube seal lips are completely inside the firewall and completely pulled all the way through the firewall.

If necessary use a small flathead screwdriver and a pair of needle nosed pliers to pull them through over the firewall.

Place the supplied 3/8”nylon spacers on the studs & attach pedal.

Push the small diaphragm into the sound tube and completely seat it. The clear membrane film should be on the outside. Be sure not to puncture the film as the diaphragm cap and clear membrane are designed to seal the sound tube and inlet pipe from debris or air entering the sound tube and inlet path.

Note running without sound tube sealed with diaphragm cap will result in unmetered air entering the inlet path.

Diaphragm cap installed

Diaphragm cap installed

Remove the inlet pipe from the throttle body to the air box first. Drill pilot hole first then with supplied bit drill so bottom of the hole is 1/8" above the seem in location marked in picture. Video explains how to drill the plastic intake for best results. Clean up the edges of the hole of any plastic burrs and blow out intake. Install the grommet and insert the greased hose short barb from the inside and push on the sound tube while hold the hose barb in place. The supplied grease will help getting these parts together. The sound tube should be pressed on tight to the hose barb and flush to inlet face so there is no movement. Use the zip to secure the end of the sound tube to hose barb for extra security. Install the other end of the sound tube through the firewall before reinstalling the inlet pipe to throttle body and airbox. This will give slack needed to install the firewall end. Pictures below show the location of hole drilled.

After rubber grommet is installed push the 1” hose barb into the grommet from the inside with supplied grease to help seat and seal.

Apply some of the supplied grease inside the grommet and sound tube. Holding the hose barb from inside push the sound tube on and completly seat so the sound tube is flush to the inlet, and hose barb is fully seated inside against the grommet. There should be no play once installed. Use supplied zip tie on the end of the sound tube for extra security.

Reinstall the inlet elbow and clamps with Sound tube attached, and then install the sound tube over the hard-plastic OEM tube previously cut and installed into the firewall from Step 1.

Use supplied grease or a soap & water solution to facilitate the fit.

This is friction fit secure with supplied zip tie.

The installed upper sound tube is now visible in the image and the install is now complete.

We appreciate your business and hope you enjoy the increased rotor whine!

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