Product Details:  Fingertip control over how loud your shifts are! By simply turning the lower ring of the cap, you can adjust how much air is vented to the atmosphere or to the inlet, giving you complete noise control over your shifts!

For cars with sensitive air-flow meters, you can dial in the valve to eliminate common problems normally associated with aftermarket valves... and still get a great sound.

No tools needed for spring adjustment. Spring adjustment is achieved by a unique mechanism contained completely within the valve, meaning that no tools are required for adjustment. This also ensures the profile remains as low as possible, as the cap does not move up and down when adjusting.

Unique piston seals achieve the best possible seal on both ends of the piston. Now, as well as our acetal piston seat, a low friction, lubricant-impregnated polymer piston ring is incorporated. This system is far more reliable than o-rings, which require frequent maintenance and replacement.

Tight engine bays are NO problem! The vacuum nipple is free to rotate through 360 degrees to make fitting easier.

Includes:

Stealth FX blow-off valve
38mm o-ring
3 x M5 grub screws
3 x M5 nuts

Fits:

Ford Laser TX3 Turbo 4WD KE - KHII (1987 – 1993)
    -Required adaptor: 5320 and 5220
    -Direct Bolt On

Ford Telstar TX5 Turbo AS - AV (1986 – 1991)
    -Required Adaptor: 5601
*Can be fitted to your TX5 by welding a steel pipe adaptor to the factory steel pipe leading up to the throttle. A short section of weld-on pipe is supplied with BOVs 1001 - 5, and is available as optional part no. 5601 for others*

Holden VL Commodore Turbo (1986 - 1988)
    -Required Adaptor: 5601
*Since there is no factory fitted bypass valve, installation of a blow-off valve is a custom job, requiring a short length of steel pipe to be welded onto the inlet piping between the turbo and the throttle.*

Mazda 626 and MX-6 Turbo (1986 - 1991)
    -Required Adaptor: 5601
*The 626 and MX-6 turbos have a small factory bypass valve mounted very near the turbo itself, and its location is not suitable for fitting an aftermarket valve. Fitting a GFB blow-off valve to your 626 or MX-6 requires that a short section of steel pipe be welded onto the intake between the intercooler; if there's one fitted; and the throttle. The BOV will then secure on this pipe. Weld-on pipes are available in steel, to suit factory inlet plumbing, as well as aluminium and stainless steel to suit custom intercooler plumbing*

Mazda RX-7 S4 & 5 (1986 – 1991)
    -Required Adaptor: 5601, 2 or 3
*Custom Installation: usually involve fabricating a replacement turbo-intercooler up-pipe with a 25.4 mm pipe welded on to mount the GFB valve. When using a GFB BOV on an RX-7 with a front mounted intercooler, the BOV should be custom installed by welding a short section of pipe onto the intercooler plumbing*

-When using the factory engine management computer, The GFB Plumback and Hybrid are recommended since they can be used successfully on air-flow metered vehicles.

Mitsubishi Starion Turbo JA - JD (1982 - 1987)
    -Required Adaptor: 5601
*Because there was no factory BOV, fitting one will require welding a short length of steel pipe somewhere between the turbo and the throttle, on a non-intercooled Starion, or between the intercooler and the throttle on a JD Starion. This kind of work can be easily and economically carried out by a workshop that's familiar with modified cars.*

Mitsubishi Cordia GSR Turbo AA - AC (1984 – 89)
    -Required Adaptor: 5601
*The Cordia wasn't fitted with a blow-off valve as standard so fitting a GFB BOV can improve after-gear-change throttle response when driving hard. It will also prevent compressor surge and of course provide the characteristic ‘PSSH' noise that turbo cars like the Cordia are all about! Fitting a GFB blow-off valve to your Cordia requires that a steel pipe be welded onto the intake plumbing between the turbo compressor outlet and the throttle, after the intercooler if one has been fitted. This kind of job can easily and economically be carried out by a performance oriented workshop.*

Mitsubishi CC Lancer GSR (1992 - 1996)
    -Required Adaptor: 5335 and 5233
    -Direct Bolt on
*Lancer GSRs use a factory valve which is designed to leak at boost levels higher than factory, so it is worthwhile replacing if you plan to increase boost levels. GSRs have no problem with vent-to-atmosphere blow-off valves*

Nissan S13 Silvia & 180SX CA18DET
    -Required Adaptor: 5601, 2 or 3
*To fit a GFB blow-off valve to your Silvia or 180', weld a short section of steel pipe onto the intake between the intercooler and the throttle, onto which the BOV will secure*

Nissan S13 Silvia & 180SX SR20DET
    -Required Adaptor: 5335
    -Direct Bolt On

Nissan Skyline GTS-t R32
    -Required Adaptor: 5102
    -Custom plumb back plumbing required

Nissan Pulsar GTi-R N14 (1990 – 1994)
    -Direct Bolt On
*Important: the GTi-R's quad throttle bodies mean that the engine vacuum under idle and cruise conditions is less than almost any other car – proof that they really do reduce intake flow restriction! However, this means that to work sucessfully, any GFB BOV fitted to a GTi-R must first be fitted with a lighter spring – the one usually fitted to the GFB plumback BOV*

N12 Pulsar ET (1984 – 1987)
    -Required Adaptor: 5601
*Fitting a GFB BOV to your ET is simple, just weld a short section of steel pipe (aluminium and stainless steel also available) to the intake system somewhere between the turbo and the throttle, and after the intercooler if there's one fitted. The GFB BOV then secures onto this pipe. Connect up a vacuum lineto the BOVs vacuum nipple and you're done!*

Nissan Z32 300ZX Twin-turbo
    -Required Adaptor: 5335
    -Direct Bolt On

Subaru WRX MY94-96
    -Required Adaptor: 5320 and 5220
 *This particular model has a very small factory valve, using 19mm internal diameter hoses. The metal elbow fitting that feeds the factory BOV is even smaller through the bore, about 15mm. It is quite straightforward installing an atmosphere-venting valve, as the plumb back hose is simply plugged (using the 20mm 5520 plug) and the valve is fastened to the factory hose*

MY97-98 WRX and Version 3-4 STi
    -Direct Bolt On
*Blow-off valve installation on this model is very easy, the factory valve is hose mounted and secured with hose clamps. GFB units will fit straight back into the factory position*

MY99-00 WRX and Version 5-6 STi
    -Required Adaptor: 5101
    -Direct Bolt On
*When installing valves with plumb back fittings on this model, it is a good idea to replace the factory spring-type hose clamp on the plumb back hose with a more substantial band-type*

Subaru Forester GT (MY98 - 00)
    -Required Adaptor: 5101
    -Direct Bolt On
*Fitting a GFB blow-off valve to your Forester is simple. Using a GFB Forester GT/MY99-00 WRX flange mount adaptor, which bolts on in the factory BOV position on the intercooler*

Subaru Forester GT (MY01 - 02)
    -Required Adaptor: 5101
*Fitting a GFB blow-off valve to your MY01 - 02 Forester GT is simple. Using a GFB Forester GT (MY01-02) flange mount base adaptor, which bolts on in the factory BOV position on the intercooler*

*The Stealth FX and Deceptor Pro are a direct bolt-on, while other blow-off valves in the range may require additional plumb back hoses or modfication to the original hose*

Subaru Forester XT (MY03 - 04)
    -Required Adaptor: 5107
    -Direct Bolt On
*Fitting a GFB blow-off valve to your Forester XT requires the use of a GFB Forester XT flange adaptor*

Toyota Celica GT4 ST205 (1994 – 1995)
    -Required Adaptor: 5335
*fits in place of the factory unit requiring only minor modifications to the factory rubber hoses or a replacement hose. While it won't give you a measurable power increase, it will give you an improvement in throttle response that you can feel*

*All of the GFB BOVs fit in place of the factory unit requiring only minor modifications to the factory rubber hoses or a replacement hose.*

Toyota Soarer JZZ30 Twin Turbo 1JZGTE
    -Required Adaptor: 5330 and 5105
    -Direct Bolt On

*easily fitted in place of the standard BOV using the adaptors recommended above*

Toyota Supra JZA80 2JZGTE
    *will require a custom installation using additional rubber hoses (available from any auto parts store)*

Volkswagen - All 1.8 Turbo models (1996 – Current)
    -Required Adaptor: 5325 and 5225
    -Direct Bolt On
1) On all VW turbo engines, the factory plastic Bosch diverter valve is installed in the reverse direction to conventional bypass valves, with boost pressure entering the side of the valve and dumping through the bottom. Therefore when installing a GFB valve, it must be installed in the REVERSE direction compared to the factory one (boost must enter the GFB unit through the bottom, and dump through the side). This is essential for the valve to operate properly. Incorrect orientation of a GFB valve will prevent the piston from opening.
2) Many of the 1.8T engines use crimped-on hose clamps on the factory diverter valves, which are not re-useable. New hose clamps are required for installation in such cases.

Additional Notes:

*Blow-off valves 1001 - 1005, 1008 and 1025 can be custom fitted by welding a short length of 1" steel pipe onto the inlet plumbing.