Holley's high-flow dual-port boost control kit pairs two pre-installed high-flow solenoids on a black-anodized billet manifold. A dual O-ring sealing design prevents boost leaks, and the solenoids are driven by Pulse Width Modulated (PWM) outputs from the ECU.
Specifications:
- Configuration: Dual solenoid, black anodized billet manifold
- Port Size: 1/4" NPT push-lock fittings (x2)
- Connectors: Two pre-terminated connectors that plug directly into the solenoids, with extra pins for Holley EFI ECU connectors
- Flow: Up to ~40% more flow than comparable dual designs and up to 90% more than conventional 3-port solenoids
- Part Number: 557-201
In the Holley EFI software, select the "Dual Holley" drop-down for solenoid configuration. It's not advised to use the PWM+ outputs on an HP ECU — use the PWM- outputs instead. On a Dominator ECU, use either the PWM- outputs or a PWM+ output on the J2B connector.
FAQ
How does this kit differ from a standard 3-port solenoid?
Its proprietary dual-port design flows nearly 40% more than comparable dual designs and up to 90% more than conventional 3-port boost control solenoids.
How do I set this up in the Holley EFI software?
Select the "Dual Holley" drop-down option for solenoid configuration.
Which ECU outputs should I use on an HP ECU?
Use the PWM- outputs rather than the PWM+ outputs on an HP ECU.
What connections are included?
Two pre-terminated connectors that plug directly into the solenoids, plus extra pins for the Holley EFI ECU connectors.
