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Manley Extreme Duty Exhaust Valves for Chevrolet LS1/LS2 LS6 Heads - Part Number 11681-8
When it comes to performance and durability, Manley Performance has set the bar high for over 40 years. Their Extreme Duty Exhaust Valves, specifically designed for Chevrolet LS1, LS2, and LS6 heads, are a testament to their commitment to quality and innovation in the automotive industry.
Exceptional Quality and Design
Manufactured using a special "Race Series" alloy, these stainless steel valves are engineered to excel in even the toughest conditions. The 11681-8 valves are not just built for looks; they feature:
- Chrome Stems: Gorgeous and durable, ensuring longevity.
- Swirl Polished Under Heads: Enhances airflow for improved performance.
- Fully Hardened Tips: Designed to withstand extreme conditions.
- Machined Combustion Faces: For precision and efficiency.
- Controlled Margin Heights: Optimizes performance across a range of applications.
- Exact Stem to Seat Concentricity: Guarantees a perfect fit for maximum effectiveness.
Extreme Duty Performance
The Extremealloy material used in these valves offers superior hot hardness and high-temperature strength, making them perfect for high-boost applications where exhaust gas temperatures can soar. Whether you’re building a street machine or a race car capable of over 1000 horsepower, these valves are designed to meet your needs.
Key Specifications
- Part Number: 11681-8
- Material: Stainless Steel
- Application: Chevrolet LS1, LS2, LS6 Heads
- Valve Type: Extreme Duty Exhaust Valve
Fitment and Installation
Before installation, it’s crucial to check your valve guide size to ensure proper valve stem to guide clearance. In some cases, honing the guides may be necessary when replacing stock factory valves. This step is essential to achieve optimal performance and longevity from your new valves.
What Customers Are Saying
Customers have praised the Manley Extreme Duty Exhaust Valves for their exceptional performance and reliability. Many have noted significant improvements in airflow and engine response, making them a popular choice among enthusiasts and professionals alike. Here’s what some users have shared:
- "These valves are a game changer! My LS build has never run smoother." - A satisfied customer
- "Top-notch quality! I trust Manley for all my performance needs." - A performance enthusiast
- "I noticed a big difference in throttle response after installing these valves." - A racer
Upgrade your LS engine with the Manley Extreme Duty Exhaust Valves and experience the performance boost that comes from quality engineering and design.
⚠ 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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