Cobb Subaru EJ TGV Shaft Seal Kit - 443700

The COBB Subaru EJ TGV Shaft Seal Kit (Part #443700) is a precision-engineered sealing solution designed specifically for Subaru EJ-series turbocharged engines. If you own a Subaru WRX or WRX STI equipped with the EJ engine family, the tumble generator valve (TGV) shaft seals are a known wear point — and failed or degraded seals can lead to boost leaks that rob power and consistency. COBB's purpose-built kit addresses this directly with a quality replacement that's designed to fit and seal correctly the first time.

Key Features & Benefits

• Billet Aluminum Construction: The COBB TGV Shaft Seal Kit consists of two billet aluminum plates, offering superior durability compared to the OEM plastic or lower-grade alternatives. Billet aluminum resists warping under heat cycling, which is critical in the high-temperature environment of a turbocharged intake tract.
• Anodized Black Finish: Each plate is anodized black for corrosion resistance and a clean, professional appearance under the hood — important for show builds and daily drivers alike.
• Laser Etched Identification: Each plate is laser etched on the end, making identification and future servicing straightforward without guesswork.
• Addresses a Known EJ Weakness: TGV shaft seals are a documented failure point on EJ-platform Subarus, especially on higher-mileage or modified examples. Replacing worn seals can restore boost integrity and eliminate related air/boost leaks.
• CARB Compliant: This kit carries CARB EO Number D-660-236, meaning it meets California Air Resources Board standards — an important consideration for California residents and emissions-tested vehicles.
• Regularly Stocked: Unlike many specialty Subaru performance parts, this kit is regularly stocked and available for prompt shipment.

Specifications

• Brand: COBB Tuning
• Part Number: 443700
• SKU: COBB443700
• UPC: 731946517733
• Material: Billet aluminum, anodized black
• Quantity Included: Two (2) billet aluminum plates
• CARB EO Number: D-660-236
• Application: Subaru EJ-series turbocharged engines

Fitment

The COBB EJ TGV Shaft Seal Kit is designed for Subaru vehicles equipped with the EJ-series turbocharged engine. Based on available fitment data from multiple sources, confirmed applications include:

• 2008–2014 Subaru WRX
• 2008–2021 Subaru WRX STI

Additional EJ-platform Subaru models such as the Forester XT and Legacy GT have been referenced in relation to this kit's broader EJ application range, though buyers with those vehicles should confirm compatibility with our fitment team before ordering. This kit is specific to the EJ engine family — it is not intended for FA-series engines found in 2015+ WRX models. If you're unsure whether your Subaru uses an EJ engine, contact our team and we'll verify fitment before your order ships.

What's in the Box

• Two (2) billet aluminum TGV shaft seal plates, anodized black with laser etching

Why Buy from ThreePiece.us

ThreePiece.us has been serving performance and enthusiast customers since 2014, with 10,000+ customers and a team that genuinely knows vehicles and fitment. When you order the COBB EJ TGV Shaft Seal Kit from us, you get:

• Free Shipping on every order — no minimum required.
• Affirm Financing — split your purchase into manageable payments, with 0% APR options available. Great for bundling multiple maintenance or performance parts in a single order.
• Expert Fitment Support — not sure if this kit fits your specific build year or trim? Call or email our team and we'll confirm before you buy. We'd rather take 5 minutes to verify fitment than have you deal with a return.
• In-Stock Availability — this product is regularly stocked, so you're not waiting weeks for a special order on a straightforward maintenance item.

Frequently Asked Questions

What exactly are TGV shaft seals, and why do they need replacing?

TGVs (tumble generator valves) are butterfly-style valves located in the intake manifold of EJ-series Subaru engines. The shafts these valves rotate on pass through seals, and over time — especially with heat cycling and age — those seals can degrade and allow boost or air leaks. On a turbocharged engine, even a small boost leak can cause inconsistent power delivery, boost spiking, or poor fuel trims. Replacing the shaft seals restores the integrity of the intake tract.

Does this kit fit both the WRX and the STI?

Yes. The COBB 443700 TGV Shaft Seal Kit fits 2008–2014 Subaru WRX and 2008–2021 Subaru WRX STI. Both models use the EJ-series engine that this kit is designed for. If your WRX is a 2015 or newer (FA-series engine), this kit does not apply — reach out to our team for guidance on the correct part for your vehicle.

Is this kit legal for use in California?

Yes. The COBB EJ TGV Shaft Seal Kit carries CARB EO Number D-660-236, indicating it has received California Air Resources Board executive order approval. California residents can purchase and install this kit without emissions compliance concerns.

How many sealing plates does the kit include?

The kit includes two (2) billet aluminum plates — one for each bank of the EJ engine's TGV assembly. Both plates are anodized black and laser etched for easy identification during installation.