Ignitions and Electrical› Distributors, Magnetos and Crank Triggers
Holley
8IN 12-1X Crank Trigger Kit BBC Hall Effect
SKU: H00E 556-170
Moderate — 2–4 hours
Description
Part #: 556-170
Upgrading to an MSD Flying Magnet Crank Trigger Kit will deliver the precise and reliable signal that a high performance engine requires. This kit gives you the ability to control timing electronically through a Holley EFI ECU (or other standalone engine management system / ignition controller). At the heart of the kit is the 3-wire Hall-Effect Sensor that is easier to set up, less susceptible to EMI/RFI interference/noise, and less likely to have false signals than other methods (Distributors and VR Magnetic Sensors). In addition, they are less prone to mechanical failure since there are no wear parts. With the included high quality timing pointer and the use of a direct bolt-on, degreed balancer (see below list for recommendations), you'll be able to adjust timing in the precise increments required for your engine.
Features:
- Most accurate way to trigger your electronic fuel injection (EFI), can be installed as 12-1 or 12x
- Powerful magnets embedded in a 3/8-inch thick billet 6061-T6 aluminum trigger wheel
- 3-wire Hall-Effect Sensor that is not easily susceptible to EMI/RFI Interference
- Engine specific kits include a direct bolt-on billet aluminum pick up bracket
- Rigid mounting that will not flex and cause timing fluctuation
- Easy to install much like traditional MSD Crank Trigger Kits
- Included installation instructions cover mechanical setup and provide step-by-step Holley EFI Software Setup
For Big Block Chevrolet
Fitment
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Specifications
| Brand | Holley |
| Part Number | H00E 556-170 |
| Weight | 3.23 lb |
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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