Advanced Engine Design 5065 6.5 Power Valve for Holley Carburetors

The Advanced Engine Design 5065 is a high-quality single-stage power valve designed specifically for Holley performance carburetors. This vacuum-operated fuel enrichment valve is rated at 6.5 inches of mercury (Hg), meaning it opens when manifold vacuum drops to 6.5 inches or lower, providing additional fuel during heavy loads and wide-open throttle conditions.

Key Features:

• Single-stage design with 6.5 Hg vacuum rating for precise power enrichment timing
• High-flow construction ensures optimal fuel delivery when engine demands increase
• Vacuum-actuated diaphragm design responds quickly to changing engine loads
• Includes gasket for proper sealing and installation (1/2-28 thread size)
• Direct replacement for Holley carburetor power valves
• Designed to improve part-throttle drivability while maintaining fuel economy during cruising

Power valves are a critical component of the Holley carburetor metering system, working in conjunction with the power valve channel restrictors (PVCR) to provide additional fuel enrichment when manifold vacuum drops during acceleration or heavy load conditions. This allows the use of smaller main jets for better fuel economy at part throttle, while still providing the extra fuel needed for optimal performance at wide-open throttle. The 6.5 rating makes this valve ideal for engines with moderate vacuum readings at idle (typically 13 inches Hg divided by 2).