GFB Deceptor Pro II Blow-off Valve (part T9503) - Manual (Page 2)

Fitting Instructions for GFB Deceptor Pro II (part # T9503)
(fits MY01–07 WRX, MY01-on STi, and MY05-08 Forester XT)
Included in the T9503 kit:

Deceptor Pro II blow-off valve

Electronic in-car volume controller

Double sided mounting tape

2 x stainless steel mounting bolts
Thank you for purchasing the GFB Deceptor Pro II blow off valve. We highly recommend that you familiarize
yourself with the operation and adjustments of the Deceptor Pro II before installing it.
Installing and wiring the in-car volume controller
1) Test the unit before installation by connecting the Deceptor Pro II’s plug to the in-car controller. Connect the
red wire to the positive terminal of your car’s battery or a 12V source. Connect the black wire to the negative
terminal. Upon initial power-up, the unit will perform an open/close cycle before reverting to the position
indicated on the controller dial. By turning the dial and watching through one of the valve’s venting outlets,
you will see the inner sleeve move to open or close each of the venting ports alternately, which is how the
venting volume is adjusted.
WARNING: Do not manually rotate the noise adjustment, always apply power and use the controller
to change the venting bias. When testing your Deceptor Pro II, DO NOT put fingers or foreign
objects through the trumpet or plumb back ports. Doing so may result in personal injury or damage
to the blow-off valve.
2) Find a suitable location on or around the dashboard, steering column or instrument binnacle for your in-car
volume controller. Clean both mating surfaces with Methylated Spirits or similar cleaner and secure the
controller using the supplied double-sided tape. Press hard and hold the unit for about 30 seconds, and note
that it takes up to 24 hours for the tape to develop a strong bond.
3) Using a multi-meter or voltmeter, find a suitable power wire that reads 12V only when the ignition is turned
on. Solder the end of the volume controller positive (red) wire to the 12V source. It is possible to use a wire
tap or crimp instead, but soldering is the most reliable joint. Make sure to insulate the joint properly.
4) Find a suitable bolt on the body/chassis and connect the unit’s ground (black) wire to it.
5) At this point you should plug the Deceptor Pro II back into the in-car volume controller, and test its operation
again to ensure the electrical connections are good. Make sure the unit powers on and off with the ignition.
6) Unplug the Deceptor Pro II and pass the controller’s extension lead through the firewall into the engine bay.
Often there is an existing grommet that can be used for this purpose. In any case, it is important to ensure that
the lead is protected where it passes through the firewall to prevent wear or damage.