Solenoid Boost Control

The Holley Solenoid Boost Control (Model HLY557-200) is a precision 3-port boost management solenoid engineered for high-performance EFI systems running Holley Dominator and HP EFI platforms. This component is essential for tuners and engine builders who demand active boost regulation in naturally aspirated and turbocharged applications. By electronically controlling boost pressure delivery, the solenoid boost control enables programmable boost curves that optimize power delivery across the entire RPM range while protecting engine internals from over-boost conditions.

The 3-port solenoid design directs boost pressure signals to the wastegate or blow-off valve with millisecond response times, allowing the engine control unit to dynamically modulate turbocharger output based on real-time data inputs. Included fittings eliminate guesswork during installation, and the compact 3.3 x 3.3 x 5.7 inch form factor fits seamlessly into tight engine bay layouts without requiring extensive fabrication. This solenoid integrates directly with Holley's advanced closed-loop boost control logic, enabling smooth transitions between load conditions and precise target boost maintenance under varying atmospheric and thermal conditions.

Performance builders, professional tuners, and serious enthusiasts benefit most from this solenoid when building street or competition engines that require repeatable, programmable boost management. It pairs directly with Holley Dominator EFI and HP EFI systems, making it the natural choice for OEM-quality boost control without standalone controller complexity. Installation requires basic pneumatic line routing and secure ECU integration—all straightforward tasks for systems already equipped with Holley's fuel injection platform.