What is Crank Trigger Ignition and How Does It Affect Your Pulley Setup?

If you're building a serious performance engine — whether it's a race-prepped small block, a supercharged LS, or a high-RPM big block — there's a good chance you've considered or already spec'd a crank trigger ignition system. And if you're running a March Performance pulley system, there are a few things you need to know before finalizing your front drive setup.

What Is Crank Trigger Ignition?

A crank trigger ignition system uses a magnetic pickup sensor and a trigger wheel mounted to the crankshaft damper or a dedicated hub to precisely time ignition events. Unlike a distributor, which can have mechanical slop and timing variation at high RPM, a crank trigger reads timing directly from the crank — giving you more accurate, more consistent spark timing at every RPM level.

The result is more precise ignition control, which translates to more power, better throttle response, and improved reliability — especially at high RPM where distributor timing variation becomes most pronounced.

How Crank Triggers Interact with Your Pulley Setup

The trigger wheel on a crank trigger system mounts either to the front of the harmonic damper or to a separate hub that mounts to the crankshaft snout, ahead of the damper. This is where it intersects with your March Performance pulley system — specifically the crank pulley and damper selection.

Key considerations:

• Damper diameter and trigger wheel clearance — the trigger wheel needs to spin past the pickup sensor with minimal clearance. Your crank pulley cannot interfere with the sensor or trigger wheel mounting
• Crank pulley depth and offset — if you're running a crank trigger hub, it may change the effective offset of your crank pulley, requiring a different pulley or a spacer to maintain proper belt alignment with the rest of the March system
• Hub mounting — some crank trigger systems use a dedicated billet hub that replaces the factory damper nose. Verify compatibility with your March Performance system before ordering

March Performance Crank Pulleys

March Performance offers crank pulleys in multiple configurations to accommodate different damper types and snout lengths. Our pulleys are CNC machined to precise dimensions, which makes it straightforward to calculate offset changes when adding a crank trigger hub to your setup.

If you're planning a crank trigger build, call our tech line at 1.888.729.9070 before ordering your pulley system. Tell us which crank trigger system you're using, your damper make and model, and whether you're using a hub-mount or damper-mount trigger wheel. We'll help you select the correct crank pulley to maintain proper alignment across your entire March Performance serpentine system or pulley and bracket kit.

All Engine Families Covered

Crank trigger setups are common across all engine families March Performance supports. Browse our full pulley lineup: Small Block Chevy, Big Block Chevy, Chevy LS, and Small Block Ford. Call 1.888.729.9070 for crank trigger specific tech support.