Precise timing controlHolley EFI dual-sync distributors are built with two Hall effect sensors for crankshaft and camshaft signals. The distributors can be used as just a crankshaft speed input, as well as providing a camshaft sync signal for sequential fueling operation. Also, they can be used for crank and cam signals for coil-on-plug applications. These units feature CNC-machined billet aluminum housings with integrated LEDs for easy setup, a hardened steel distributor gear, and precision-machined shutter wheels that ensure accurate timingeven at very high rpm. Designed to be plug-and-play with their systems, Holley EFI dual-sync distributors may be used with other EFI systems that support Hall effect crankshaft and camshaft sensors. Dozens of models are available; order the one recommended for your vehicle/engine application.