Howards "Extreme Black" Severe Application Valves
Engineered for high rpm and high horsepower applications. Extreme Black valves feature a special black nitride process and are perfect for high temperatures (they run cooler which improves valve life). Great for nitrous, turbo and supercharger applications. For naturally aspirated motors these valves will give you a much greater cylinder flow for good horsepower gains. They start as a one piece forged, high temperature, high nickel, stainless steel alloy. CNC finished to strict tolerances, making these valves the choice for the most demanding race classes. The black nitride micro-hardness is higher than the stainless steel base material. No process can match it for surface hardness. Surface finish is smoother than with chromed stems, having less friction between stem and guide. Nitriding is not a coating, it is a process where it actually becomes part of the steel.
• High nickel stainless alloy 1 piece forgingsPart Type: Intake Valve
• Special black nitride process
• Great for naturally aspirated applications
• Great for nitrous applications
• Great for turbo applications
• Great for supercharged applications
• Designed for high horsepower applications
• Runs cooler, improves valve life
• Fully CNC machine finished
• Surface finish is smoother than chrome
• Higher micro-hardness than stainless
• Undercut stems for increased flow
Style: Howards Cams "Extreme Black" Severe Application Valves
Application: Chevrolet Small Block V8
Head Diameter: 2.080"
Stem Diameter: 11/32" (.3415")
Installed Height: +.100"
Overall Length: 5.011"
Material: 21-4N High Nickel Stainless Steel
1-Piece Design: Yes
Hard Chrome Stems: No
Undercut Stem: Yes
Black Nitrided: Yes
Swirl Polished: Yes
Lock Groove Type: Conventional
Lock Groove Quantity: Single
Tip Length: .250"
Under Head Angle: 10 Degrees
Under Head Radius: .375"
Seat Width: .100"
Top of Head: 6 Degree Dish
Weight: 125 grams
Manufacturer: Howards Cams & Racing Components
Manufacturer's Part Number: 20811N
Weight: 0.30 lbs.
Warranty: Race Application, No warranty expressed or implied.
Quantity: Sold as Each