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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$725.43
LAST ONE! Est Ship 4-7 days. In stock at 2 locations (5 available)

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Description

Cam Position Sensor - 12 mm x 1.00 Thread - Target / Bracket Included - Flying Magnet - Holley EFI Kits - Plus 0.600 to 1 in Camshaft Height - Big Block Chevy - Kit


Data: v2 - Desc: v4.2 - Upd: 2026-11-08 02:16:05

Data: v4.2 - Upd: 2026-11-08 06:33:26

Features

Images are supplied by the manufacturer and may be generic. While all efforts are made to provide accurate pictures, there may be differences in the actual product, such as colour, quantity, version, or included components. Please carefully review the description and specifications for details on inclusions or any variations. Some items may be sold individually or in sets, and images may occasionally depict additional products or quantities not included in your purchase. For assistance or clarification, please contact customer support.

Specifications

Reference Information

Reference Data (Provide these details to our support team)
Brand Name/s Holley, Hilborn, Holley Efi, Retrobright, Terminator X
StreetFX SKU hly556-121
SFX Item ID 4783231
Accounting SKU hly-556-121
Manufacturer SKU 556-121
Manufacturer UPC 090127725054
Alternative References 556-121, HLY-556-121, HOL556-121

Camshaft Sync 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

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

Product Attributes
BrandHolley
Manufacturer's Part Number556-121
Part TypeCamshaft Sync Pickup Kits
Product LineHolley Chevy Camshaft Sync Kits
UPC090127725054
Non-Magnetic Pickup IncludedYes
Wiring Harness IncludedYes
Mounting Hardware IncludedNo
QuantitySold as a kit.
NotesBig 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.

Compatibility

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