GFB Deceptor Pro II (part T9520) - Manual (Page 2)

Installing the blow-off valve
The standard inlet and outlet of the GFB Deceptor Pro II T9520 are 20mm in diameter, which is a suitable
size for fitting into ¾” (19mm) I.D. hose. For different mounting options, a list of the adaptors available is
shown below, but if in doubt, check out the adaptors page on our website
www.gfb.com.au , or consult your
local dealer.
T9520 is suitable for custom installations, and also has the same size fittings as the factory valves on the
following vehicles (some applications may require the factory hoses to be extended or modified):

Subaru WRX/STi MY94-96

Subaru Legacy RS Turbo MY89-93

Ford Laser TX3 KC-KH

Mazdaspeed Miata SE

Mazda RX7 Series 4-6

Toyota Supra JZA80
For cars without a factory fitted bypass valve, a
location for the Deceptor Pro II must be found
on the piping between the turbo outlet and the
throttle body, and a suitable adaptor must be
welded in that location to which a ¾” hose can
be connected. A hose to connect the Deceptor
Pro II recirc outlet must also be fitted to the
piping before the turbo (after the airflow meter,
if one is installed).
NOTE: GFB recommends mounting the BOV
closer to the throttle body rather than the turbo,
since some factory turbo piping can cause
pressure
drops which may affect the
performance of the valve. If an intercooler is
used, it is preferable to mount the valve after the
intercooler, before the throttle.
1)
Push the base inlet of the Deceptor Pro II into the boost pressure source hose (i.e. from between the
turbo and throttle body), and secure with a hose clamp.
2) Connect the recirc outlet on the side of the Deceptor Pro II (opposite the trumpet) to the recirc hose
that leads back to the turbo intake and secure with another hose clamp.
3)
Connect the vacuum nipple on the top of the Deceptor Pro II to a suitable manifold vacuum source
(after the throttle body), using rubber or silicone vacuum hose of at least 4mm I.D. Try to avoid
attaching any other hoses and t-pieces to the vacuum hose and keep it as short as possible, as this will
ensure rapid response from your GFB valve. DO NOT CONNECT THE VACUUM HOSE TO
BOOST CONTROL, FUEL PRESSURE REGULATOR OR BRAKE BOOSTER HOSES.
Adaptors Available
Base (inlet) adaptors:
5325 – 25mm hose inlet
5330 – 30mm hose inlet
5333 – 33mm hose inlet
5335 – 35mm hose/1” pipe mount base
5338 – 38mm (1.5”) pipe mount base
Recirc (outlet) adaptors:
5225 – 25mm
5230 – 30mm
5233 – 33mm