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Manley Severe Duty Exhaust Valves for Chevrolet LS1/LS2 with LS6 Heads
Upgrade your Chevrolet LS engine with the Manley Severe Duty Exhaust Valves (Part Number: 11673-8). With over 40 years of experience, Manley Performance has set the standard in the industry, and their stainless steel valves are crafted to deliver exceptional performance and durability.
Features That Make a Difference
- High-Quality Materials: Made from Manley’s exclusive "Race Series" alloy, these valves are designed to withstand the most demanding conditions.
- Exceptional Design: Each valve features polished under heads, fully hardened tips, and precisely machined combustion faces, ensuring superior airflow and performance.
- Extreme Duty Option: For those pushing the limits, the "Extremealloy" material offers enhanced hot hardness and temperature strength, perfect for high-boost applications.
Benefits of Choosing Manley Valves
Whether you're building a street performer or a high-powered race machine, Manley valves cater to a wide range of applications. They outperform competitors in severe environments, making them ideal for setups that demand reliability and power. These valves are suitable for everything from mild builds to jaw-dropping 1000+ horsepower race cars.
Specifications
- Part Number: 11673-8
- Material: Stainless Steel with "Race Series" alloy
- Features: Chrome stems, swirl polished under heads, hardened tips, controlled margin heights
- Applications: Chevrolet LS1, LS2 engines with LS6 heads
Fitment Information
These valves are specifically designed for Chevrolet LS1 and LS2 engines equipped with LS6 heads. Before installation, it's crucial to check your valve guide size to ensure proper valve stem to guide clearance. In some cases, you may need to hone the guides when replacing factory valves.
Customer Feedback
Customers have praised the Manley Severe Duty Exhaust Valves for their reliability and performance. Many have noted significant improvements in airflow and power output after installation. Here’s what some users are saying:
- "These valves are a game changer! My LS build has never run smoother." - Verified Buyer
- "Excellent quality and fitment. Highly recommend for any serious build!" - Performance Enthusiast
- "I’ve used Manley valves in multiple projects, and they always deliver." - Long-time Customer
Upgrade your LS engine with the Manley Severe Duty Exhaust Valves and experience the difference in performance and reliability. Don't settle for less when you can have the best!
⚠ WARNING:
Cancer and Reproductive Harm
https://www.P65Warnings.ca.gov
Make Vehicle | Model | Year |
---|---|---|
2004-2007 Cadillac CTS-V |
CTS-V | 2004-2007 |
1998-2002 Chevrolet Camaro |
Camaro | 1998-2002 |
1997-2007 Chevrolet Corvette |
Corvette | 1997-2007 |
1993-2002 Pontiac Firebird |
Firebird | 1993-2002 |
2004 Pontiac GTO |
GTO | 2004 |
Manley Performance, formerly called Manley Speed Equipment, was established in 1966 by Hank Manley shortly after his graduation from Brown University. His interest in the performance and racing traced back to 1960 when, at age 17, he rebuilt a 312 CID Ford V8 engine, installed a camshaft and three two-barrel carbs, and raced a ’56 Thunderbird on New Jersey’s streets. Initially, the company’s product lineup included stainless valves, lifters, camshafts, forged pistons, vanadium valve springs, pushrods, and timing chain kits. By 1998, Manley had outgrown its first Bloomfield, New Jersey facility and bought several acres in Lakewood, New Jersey. It was around this time that the brand’s name formally changed to Manley Performance. Nearly a decade later, the production space doubled in size.
Evolving in the Automotive SpaceLed by GM Michael Tokarchik in 2002, Manley entered the high-performance passenger car market as an OEM supplier of connecting rods for the 2003/2004 Ford SVT Mustang Cobra. Production reached 2500 rods per week without missing a single delivery date. Ford awarded Manley its highest ever supplier rating. Manley’s presence in the OEM market continued from there as a supplier for the Ford GT. After nearly 50 years since its inception, Manley continues to be globally recognized as the leading manufacturer of performance valves, connecting rods, cylinder head components, pushrods, drive and oil systems, and several other engine parts.
What is Manley’s Specialty?Manley Performance specializes in high-performance engine internals that range from stock replacements to full-on race applications. They have been the standard of the industry since their inception; a fact that still remains true now as they have ventured into new markets. Today, Manley Performance continues to re-define itself in a high-performance aftermarket industry that is constantly evolving. The brand has developed a wide range of new products for growing markets that include sport compact, Ford modular, and Chevy LS. Manley also maintains its leadership role with the traditional V8 engine business.
Get Manley Performance at Vivid RacingIf you are in need of a serious upgrade to your engine, then Manley Performance parts should be on your list. Like all of our suggested manufacturers, Manley uses the best materials available to ensure a quality part for your engine. We carry Manley connecting rods, crankshafts, pistons, and valve components. The large lineup of domestic parts includes sport compact vehicles, Ford modular engines, GM’s LS series internals, and HEMI product upgrades for Chrysler.
If you can’t find what you’re looking for or need help choosing the right part for your car, call our sales team at (480) 966-3040. We are here to make your buying experience a breeze.
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