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Holley Chevy Camshaft Sync Kits 556-121 Pickups, Hall Effect Sensor, with Bracket, 1/4 in.-20 Magnetic, 0.600 to 1 in. Raised Cam, External Dry Cam Drive, Chevy, Big Block, Kit

SKU: HLY556-121

Camshaft Sync Pickup Kits

Holley Chevy Camshaft Sync Kits 556-121 Pickups, Hall Effect Sensor, with Bracket, 1/4 in.-20 Magnetic, 0.600 to 1 in. Raised Cam, External Dry Cam Drive, Chevy, Big Block, Kit

SKU: HLY556-121

Camshaft Sync Pickup Kits
A$726.60
LOW STOCK! Est Ship 4-7 days. HURRY! LOW STOCK. This item is in limited stock at one of our distribution centres. The ETA is the approximate time required to prepare your order for dispatch.
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Description

A cam sync signal is required to run sequential fuel injection, and Holley camshaft sync kits are ready to set the firing order for top performance. Available in a choice of kits for standard cam height small block and big block Chevys, as well as raised cam height big blocks, these Holley kits fit Jesel and other external, dry timing belt cam drive systems. They provide a plug-and-play cam position signal to Holley EFI systems, but are also compatible with any EFI system which can read a digital, square-wave cam input signal. All of the kits feature unique T-nut and bracket designs that allow for complete sensor adjustment from the outside of the bracket with a single jam nut. Let your ECU know which cylinder is number one in the firing order with a signal from Holley Chevy camshaft sync kits.

Holley kits include:

* 3-wire H all-effect sensor (8 to 20 V)
* Anodized billet aluminum bracket
* Mounting hardware
* Mating connector
* Stainless steel 1/4 in.-20 "flying magnet" screw with a high-temperature, rare-earth magnet

Part Type

Cam Sync Kit - BBC w/ +.600/+1.000 Raised Cam

Data: v4.2 - Upd: 2026-10-13 18:47:39

Specifications

Product Attributes - Brand
Holley
Product Attributes - Manufacturer's Part Number
556-121
Product Attributes - Part Type
Camshaft Sync Pickup Kits
Product Attributes - Product Line
Holley Chevy Camshaft Sync Kits
Product Attributes - UPC
090127725054
Product Attributes - Non-Magnetic Pickup Included
Yes
Product Attributes - Wiring Harness Included
Yes
Product Attributes - Mounting Hardware Included
No
Product Attributes - Quantity
Sold as a kit.
Product Attributes - Notes
Big Block Chevy with 0.600 to 1.0 Inch raised cam height. For external, dry timing-belt, cam drive systems. Includes flying magnet, bracket, and pickup.

Reference Information

Brand Name/s Holley
StreetFX SKU hly556-121
SFX Item ID 4783231
Supplier Item Code 4783231
Manufacturer SKU 556-121
Manufacturer UPC 90127725054
Alternative References HOL556-121, in.-20

Compatibility

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