MSD's cam sync plugs are designed for aftermarket sequential EFI systems with coil-per-cylinder ignition. The plug installs in place of a traditional distributor, providing a hall-effect cam sync signal so the EFI system can reference the #1 cylinder, and it drives the oil pump in wet sump applications. It's plug-and-play with Holley EFI and interfaces easily with most other aftermarket EFI systems.
Specifications:
- Category: Ignition
- Engine: Ford Small Block (289/302)
- Color: Black and Silver
- Distributor Type: Cam Sync Plug
- Gear Material: Steel, Melonized QPQ Coated
- Sensor: Hall-Effect
- Ignition Box Required: EFI
- Part Number: 85221
FAQ
What does the MSD 85221 cam sync plug do?
It installs in place of a traditional distributor to provide a hall-effect cam sync signal and, on wet sump applications, drive the oil pump.
What gear does the MSD 85221 use?
It's supplied with a steel distributor gear, melonized QPQ coated.
Is the MSD 85221 compatible with Holley EFI?
Yes, it's plug-and-play with Holley EFI and can also interface with most other aftermarket sequential EFI systems.
What engine is the MSD 85221 designed for?
It's designed for the Ford 289/302 small block.

