Holley's Dual Sync distributors feature an improved shutter wheel, dual Hall effect sensors, and an MSD-style cap and rotor. Built primarily for sequential fuel injection, they can also serve as a crank trigger for TBI setups or with other EFI systems that support Hall effect crank and cam sensor inputs. The shutter wheel is pinned and welded to the shaft for durability, and the housing retains MSD shaft diameters for easy sourcing of a bronze gear.
Specifications:
- Distributor Type: EFI Dual Sync
- Sensor Type: Dual Hall effect (crank and cam)
- Housing: Polished CNC-machined billet aluminum
- Gear: Hardened steel
- Shaft Diameter: 0.500 in.
- Shutter Wheel: Precision-machined, pinned and welded to the shaft
- Setup Aid: Integrated LEDs for easy timing setup
- Cap Option: Blank cap available for Coil-On-Plug applications
- Engine Application: Big Block Chevy, tall deck
- Part Number: 565-204
Plug-and-play with Holley EFI; when used with Sniper EFI, Ignition Adapter 558-493 is required.
FAQ
Does this distributor work with Sniper EFI?
Yes, but Ignition Adapter 558-493 is required when pairing this Dual Sync distributor with a Sniper EFI system.
What engine block is this distributor built for?
It's built specifically for tall-deck Big Block Chevy engines.
What sensor technology does this distributor use?
It uses dual Hall effect sensors — one for crank signal and one for cam signal — providing precise, noise-immune timing control for sequential EFI operation.
What is the distributor shaft diameter?
The shaft diameter is 0.500 in., matching standard MSD dimensions for easy gear sourcing.
