-14%
Sold out
Click to zoom in
GSC P-D 3057-12 Manganese Bronze Exhaust Valve Guides for Porsche 996/997 Turbo - Set of 12
The GSC P-D 3057-12 provides a complete set of 12 standard-size manganese bronze exhaust valve guides for Porsche 996 and 997 Turbo engines. Exhaust valve guides operate under extreme heat and load conditions, making material selection critical for durability. Manganese bronze conducts heat more efficiently than cast iron and resists wear at elevated temperatures, helping maintain precise valve alignment and oil control over extended service intervals. The 3057-12 is the go-to choice for Porsche engine rebuilders seeking a direct OEM-dimension replacement with improved long-term performance characteristics.
Features and Benefits
- Manganese bronze alloy provides superior heat resistance for exhaust guide duty
- Standard OD fits the factory bore without additional machine work in most applications
- Set of 12 covers all exhaust valve positions in the Porsche 996/997 Turbo flat-six
- Precision-machined for consistent wall thickness and guide bore geometry
- Improved wear characteristics extend rebuild intervals versus OEM cast iron
- Trusted by professional Porsche engine builders worldwide
- Available in standard and oversize OD options from GSC P-D
Fitment
| Year | Make | Model | Engine |
|---|---|---|---|
| 2001 | Porsche | 911 Turbo (996) | 3.6L Twin-Turbo H6 |
| 2002 | Porsche | 911 Turbo (996) | 3.6L Twin-Turbo H6 |
| 2003 | Porsche | 911 Turbo (996) | 3.6L Twin-Turbo H6 |
| 2004 | Porsche | 911 Turbo (996) | 3.6L Twin-Turbo H6 |
| 2005 | Porsche | 911 Turbo (997) | 3.6L Twin-Turbo H6 |
| 2006 | Porsche | 911 Turbo (997) | 3.6L Twin-Turbo H6 |
| 2007 | Porsche | 911 Turbo (997) | 3.6L Twin-Turbo H6 |
| 2008 | Porsche | 911 Turbo (997) | 3.8L Twin-Turbo H6 |
| 2009 | Porsche | 911 Turbo (997) | 3.8L Twin-Turbo H6 |
| 2010 | Porsche | 911 Turbo (997) | 3.8L Twin-Turbo H6 |
Specifications
| Specification | Detail |
|---|---|
| Part Number | 3057-12 |
| Brand | GSC Power-Division |
| Material | Manganese Bronze |
| Style | Standard OD |
| Quantity | Set of 12 (full exhaust set) |
| Application | Porsche 996 / 997 Turbo |
| Warranty | Manufacturer limited warranty |
What's Included
- 12 x Manganese Bronze Exhaust Valve Guides (GSC P-D 3057-12)
Frequently Asked Questions
What engines does the GSC P-D 3057-12 fit?
These exhaust valve guides are designed for the Porsche 996 and 997 Turbo flat-six engines, including both the 3.6L and 3.8L twin-turbocharged variants.
Why are manganese bronze guides preferred for exhaust applications?
Exhaust guides run significantly hotter than intake guides. Manganese bronze has better thermal conductivity and wear resistance at high temperatures compared to cast iron, making it the preferred upgrade material for performance and reliability rebuilds.
Are these standard size or oversized?
The 3057-12 is standard outside diameter. GSC also produces oversize OD variants for parent bores that have been worn or previously machined.
Do I need to replace intake and exhaust guides at the same time?
Best practice is to replace both sets during a full head rebuild. GSC also offers the Porsche 996/997 Turbo intake guide set to complement the 3057-12.
Can the GSC P-D 3057-12 be used on a built or heavily modified Turbo engine?
Yes. The upgraded material is well-suited for high-boost, high-RPM applications where heat and wear on exhaust components are elevated.
How many exhaust valves does the Porsche 996/997 Turbo engine have?
The flat-six has 12 exhaust valves total, two per cylinder, so this set covers all positions.
Does installation require machine shop work?
Yes. Valve guides must be pressed out and pressed in using proper tooling and an arbor press, then reamed to the correct ID for the valve stems being used.
Is GSC P-D a reputable source for Porsche engine components?
Yes. GSC Power-Division is well-regarded in the performance engine building community, with specific application-engineered parts for European and Japanese performance platforms.
Installation Notes
- Remove the cylinder head from the engine following Porsche factory procedures.
- Press out the old exhaust valve guides using a proper piloted driver and arbor press.
- Clean and inspect the guide parent bores for wear or damage.
- Chill the new 3057-12 guides and/or gently heat the head to ease installation.
- Press new guides to the correct depth per Porsche specification.
- Ream each guide to the correct inside diameter for the valve stems being used.
- Complete valve seat reconditioning and reassemble the cylinder head.
- Torque the head to factory specifications on reinstallation.
CALIFORNIA PROPOSITION 65 WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.
GSC Power Division
GSC Power Division is a manufacturer of precision-engineered camshafts, valve springs, and valvetrain components designed for high-performance and competition engines across domestic, import, and diesel platforms. Founded by engineers with deep roots in motorsport, GSC Power Division components are machined to exacting tolerances and heat-treated to survive the demands of forced induction and high-rpm applications that destroy stock valvetrain parts. The brand is particularly well-known in the Mitsubishi Evo, Subaru STI, Nissan RB, and Toyota 2JZ communities where aggressive camshaft profiles are essential for extracting maximum power from turbocharged four-cylinder and six-cylinder engines. Whether building for drag racing, road course competition, or a high-powered street car, GSC Power Division camshafts and valve springs are a proven upgrade path. Popular Upgrades GSC Power Division S1, S2, and S3 camshafts are the most popular selections, with each profile offering progressivel...
View GSC Power Division Products
Porsche Parts & Accessories
Shop Porsche parts and accessories at Black Ops Auto Works for 911, Cayman, Boxster, Macan, Cayenne, Panamera, 718, 996, 997, 991, 992, 986, 987, 981, 982, 964, 993, 944 Turbo, GT3, GT3 RS, GT4, Turbo, Carrera, and performance Porsche builds. This collection includes exhaust systems, muffler bypass pipes, sport cats, downpipes, suspension upgrades, coilovers, sway bars, shocks, struts, brake pads, brake rotors, caliper rebuild kits, carbon fiber exterior parts, intake systems, air filters, cooling parts, wheel spacers, wheel bolts, drivetrain upgrades, engine parts, valve guides, fuel injectors, and Porsche styling accessories. Use this Porsche collection to find the right upgrade by model, chassis code, product category, brand, and driving goal. Exhaust and intake upgrades help improve sound and airflow, brake upgrades support stronger stopping power, suspension parts improve handling and ride control, carbon fiber parts add lightweight styling, cooling parts support demanding driv...
View Porsche Parts & Accessories Products
Valve Guides
Welcome to our Valve Guides collection, where you can find a wide range of high-quality products designed to enhance your automotive performance. Our carefully curated selection includes everything you need to ensure optimal functionality and longevity for your vehicle's engine components. Why Choose Our Valve Guides? Durability: Constructed from premium materials to withstand high temperatures and pressure. Precision Engineering: Designed for a perfect fit, ensuring smooth operation and reduced wear. Performance Boost: Improves engine efficiency and power output, maximizing your vehicle's performance. Wide Selection: Available for various makes and models, tailored to meet your specific needs. Featured Products Explore some of our top-rated valve guides: High-Performance Valve Guides - Ideal for racing and high-performance engines. OEM Replacement Valve Guides - Perfect for restoring your vehicle to factory specifications. Custom Valve Guides - Tailor-made options for sp...
View Valve Guides Products
Valves & Components
Browse all of our valves and valvetrain components at Black Ops Auto Works, including engine valves, valve covers, valve cover gaskets, valve guides, valve springs, retainers, valve locks, valve seals, lash caps, and related valvetrain hardware for performance builds, engine refreshes, and high-horsepower applications. Whether you are rebuilding a cylinder head, upgrading your valvetrain for higher RPM, or replacing worn valve train components, this collection is built for customers searching for engine valves, valve springs and retainers, valve cover gaskets, performance valve covers, and valvetrain upgrades. Shop Top Valvetrain Brands Find trusted brands in the valve and valvetrain category, including: GSC Power Division Supertech Brian Crower Ferrea Manley Performance Cometic Granatelli Moroso BLOX Racing These brands are known for performance intake valves, exhaust valves, valve spring kits, titanium retainers, valve guides, valve locks, valve seals, billet valve covers, an...
View Valves & Components Products