Holley Single-Stage Power Valve - Standard Flow 4.5 in. Hg
The Holley 125-45 is a standard flow single-stage power valve designed for Holley performance carburetors. This essential component operates as part of the power enrichment circuit, using engine vacuum to control its opening and closing rate.
Key Features:
- Single-stage design for reliable performance
- Standard flow configuration
- 4.5 in. Hg opening vacuum specification
- Includes gasket for proper installation
- Compatible with Holley Carburetor models 2300, 4150, 4160 & 4500
Operation: The power valve operates by monitoring engine vacuum levels. When the vacuum drops to 4.5 in. Hg or below (typically during heavy load or full power situations), the valve opens to supply additional fuel to the main system. This eliminates hesitation and bogging, ensuring smooth power delivery without drivability concerns.
Quality Assurance: Genuine Holley replacement part manufactured to OEM specifications. Modern Holley carburetors built since 1992 feature a power valve check system that protects the diaphragm from damage due to engine backfire, making this component highly reliable.