GFB WGA Internal Wastegate Actuator

The WGA is a high-performance bolt-on internal wastegate actuator designed to bring boost on sooner and hold it longer!

The WGA is all about increasing the “area under the boost curve”. With a larger diaphragm than the OEM actuator, the WGA has more “control authority” over the wastegate flap. This makes it harder for exhaust backpressure to blow the wastegate open during spool up and at high RPM, two areas of the boost curve where the factory actuator can be overwhelmed.

This benefit is particularly useful with Subaru’s factory “2-port” boost control system, which cannot effectively shut off pressure to the wastegate during spool up.

Supplied with 3 springs and a unique turnbuckle pre-load adjustment, the base boost pressure can be configured and adjusted from 5psi to 24psi for the best possible boost control.

Read on for more technical information on wastegate springs, and how the correct spring selection can improve performance.

The WGA features a longer stroke, shorter height, and more adjustment than its rivals.

WGA part # 7305 is designed to bolt on to Subaru WRX STI models from MY99-21 and will also fit most single-scroll IHI VF turbos. The 5psi and 10psi springs are installed for a base pressure of 15psi, and the 7psi spring is included in the packaging for further tuning options.

MORE ADJUSTABLE, MORE EASILY.

Setting the base spring pressure correctly for your application can have significant performance benefits, so we made sure the WGA offers the best adjustability on the market!

We supply 3 stainless steel springs that can be used in any combination ranging from 5psi to 22psi, but that’s only the beginning. Whilst other brands may offer more spring options (sold separately), changing springs to fine-tune boost pressure is time consuming and quite frankly, a pain in the butt.

That’s why we added another industry-first: turnbuckle adjustment. Because the WGA was designed with a long stroke, it is possible to use some of that extra stroke length to fine-tune the base boost pressure in a matter of minutes without swapping
springs or removing the actuator.

As an added benefit, the turnbuckle makes swapping springs so easy that it can often be done without removing the actuator from the car!

Note: that whilst this is a physical “bolt-on” product, it should be considered a tuning tool as it WILL increase boost pressure and therefore TUNING IS REQUIRED.

• Industry-first diaphragm design - the WGA’s Nomex-reinforced silicone diaphragm is designed to achieve the largest effective diaphragm area with the smallest possible outside diameter. This gives the WGA more control  authority over the wastegate flap, resulting in better boost control. It’s a bit like being the turbo’s puppet-master, rather than its puppet!
• No unnecessary bulk sounds obvious, but attention to detail in the design means the WGA is the shortest actuator on the market
• Longest stroke – with 18mm of rod travel, the WGA is suitable for controlling the largest of internal wastegates, or the extra travel can be used to further increase boost pressure without having to change springs.
• Unique pivoting rod guide – machined from PEEK (an extremely high-performance engineering polymer), the encapsulated spherical rod guide takes up significantly less height in the actuator body than other designs, whilst offering low friction and superior wear resistance.