SPDZ1 GM SQUARE - PRIMARY O2 EXTENSIONS 24" (2009-2015 CTS-V / 2004-2006 GTO / 2008–2009 Pontiac G8) - Pair of Harnesses

SPDZ1 Oxygen Sensor Extension Harnesses (Pair)

SPDZ1 Oxygen Sensor Extension Harnesses are engineered to provide a high quality, reliable solution when additional sensor harness length is required—especially during header or exhaust upgrades that relocate factory oxygen sensors downstream.

Designed with OEM-style connectors and high-quality wiring, these extensions ensure proper sensor function without cutting, splicing, or modifying your factory harness. The result is a plug-and-play installation that maintains signal integrity, prevents wiring strain, and helps keep your engine management system operating as intended.

Whether you’re installing long-tube headers or custom exhaust components, SPDZ1 delivers the durability and fitment you expect from performance-driven hardware.

Key Features

• Plug-and-play design with factory-style connectors

• Allows safe relocation of oxygen sensors during header or exhaust installs

• High-temperature, automotive-grade wiring for long-term reliability

• Prevents harness tension and potential sensor damage

• No cutting or splicing required

Sold as a pair (2 extensions included)

Vehicle Applications

2009–2015 Cadillac CTS-V

2004–2006 Pontiac GTO 

2008–2009 Pontiac G8