An Alloy Atmospheric Dump Valve to fit the Subaru Impreza 2001 onwards models including the 2009 GR STi .

Made from billet aluminium and hand polished in the UK, this atmospheric diverter valve dumps the charge-air to atmosphere creating the "Whoosh" sound most commonly associated with rally cars when the throttle is lifted. This increases both quicker throttle response and higher clamping load to maintain boost pressure more reliably.

In The Box:

1 x FMDVSUB01 Valve
1 x 34mm Blanking Plug
1 x Forge Sticker

If you wish to tune this product to fit the needs of your engine, please see the spring tuning kit below.

If you are unsure if this product is suitable for your application, please contact us.

Did You Know?

This Forge Motorsport valve relies on an internal spring in order to maintain a seal so that you have boost pressure when it is needed. If the spring is too, weak you lose power. Previously, when an engine was "chipped" or the boost pressure increased, the tuner would need to fit a stronger spring, carefully matched to the increased boost. For those running switchable software programs, there was no perfect solution.

Forge are pleased to offer a fit once and forget solution, the FMIPCV. No more changing springs, turning adjusters, or fine tuning, whilst not knowing if you have done it correctly. This works straight out the box. It will work perfectly on a standard engine, a highly tuned engine, and anywhere in between, without the need to change anything! It does it all by itself, ensuring that you always get the maximum power and perfect drivability.

If purchased in combination with this valve, we can now offer you the FMIPCV at just £42 instead of the normal selling price of £103.95 (tax and regional differences may apply). Simply select the 'Valve + FMIPCV' option to save 60%, and know that your valve will always perfectly match your engine and give optimum performance.