The Holley 8-Inch 12-1X Crank Trigger Wheel delivers the precise, reliable crankshaft signal needed to control ignition timing electronically through a Holley EFI ECU or other standalone engine management/ignition controller. The billet aluminum wheel pairs with a 3-wire Hall-Effect sensor that resists EMI/RFI interference and is less prone to mechanical failure than a distributor or VR magnetic sensor setup.
Specifications:
- Diameter: 8-inch
- Trigger Pattern: 12-1X (installs as 12-1 or 12x)
- Sensor Type: Hall Effect
- Material: Billet 6061-T6 Aluminum
- Thickness: 3/8 in
- Application: Universal (BBC/LS)
- Part Number: 556-180
This wheel is sold separately from the engine-specific pickup bracket; Holley also offers complete bolt-on crank trigger kits for Coyote, LS, and SBF applications.
Compliance: This part is legal for sale and use on Racing Use Only Vehicles — competition vehicles that are not registered and never operated on the street. It is against the law to install this part on an Emissions Controlled Vehicle (1966-and-newer California-certified or 1968-and-newer federally certified vehicles).
FAQ
What does the 12-1X trigger pattern do?
It's a magnet pattern machined into the wheel — switchable between 12-1 and 12x configurations — that gives the ECU an accurate crankshaft speed and position signal for ignition and fuel timing.
What sensor is used with this wheel?
A 3-wire Hall-Effect sensor, which is less susceptible to EMI/RFI interference and less prone to mechanical failure than a distributor or VR magnetic sensor.
Does this kit include a mounting bracket?
No. This is the 8-inch universal trigger wheel only; engine-specific bolt-on pickup brackets are included with Holley's complete crank trigger kits (Coyote, LS, and SBF part numbers).
Is this part legal for street use?
No. It is legal for Racing Use Only vehicles and cannot be installed on an emissions-controlled street vehicle.
