Process West Raw Silver Billet Tumbler Generator Valve (TGV) Delete Kit 2001-2007 & 08+STI

Process WestSKU: PWTD04
Ease of Fitment Guide: Intermediate

List Price (exc VAT): £449.99 Sale price Your Price: £539.99
In stock
Delivery Information


Tumbler Generator Valves (or "TGV" as they are most commonly referred to) can be found on Impreza WRX, Forester Turbo and Legacy GT models from 2001 onward.

Their prime purpose is to reduce emissions from cold idle to meet standards governed by the EU emissions regulations (similar regulations also exist for both the US and Japan). Whilst this may be good for the environment it does little to aid the performance of your car and it's not uncommon for the sensors and motors connected to the TGV body to fail (leading to "limp mode", CEL lights and ultimately considerable expense in replacement parts and code clearing).

The standard TGV's are similar to the design of your throttle body, encompassing twin "butterfly" valves in each tumbler housing to control air flow. Even when fully open these restrict the flow of air traveling into the cylinder head ports, reducing performance. This coupled with the possibility of sensor and motor failure mean there is good call for an improved alternative!

With the port profile machined to suit ported heads these are a simple upgrade to maximise airflow in all conditions. The upper flange surface is O-ringed for a perfect seal to either a stock or aftermarket plenum. Fuel injector ports are machined in such a way that either 11mm or 13mm diameter injectors will seat without needing any adaptors, just use the supplied Viton O-rings as required. Fuel rail mounting points are the same as stock, so it is possible to use this with other aftermarket fuel rails.

• X2 Billet Aluminium tumbler assemblies.

• X4 Inlet manifold to tumbler o rings.

• X2 Tumbler to cylinder head gaskets.

• X1 Bolt Kit to secure the manifold and tumbler castings to the cylinder heads.

• NOTE - For Impreza WRX and Forester models CEL light removal is necessary by aid of ECU adjustment from your nearest ECU Mapper.

• Removes existing TGV deletes containing butterfly valves, sensors and motors.

• Provides improved airflow from the inlet manifold through to the cylinder heads.

• Removes potential future failures with both the TGV position sensors and Motors.

• Impreza WRX 2001-2007 (ECU Remap required after fitting).
• Forester XT, XTN, 2003-2007.

Prior mechanical knowledge and specialist tools are required. Please contact us for more details prior to purchase.

Payment & Security

American Express Apple Pay Diners Club Discover Google Pay Maestro Mastercard PayPal Shop Pay Union Pay Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.